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Abstract:
Measured productivity growth increased substantially during the second half of the 1990s. This paper examines whether this increase owes to an increase in the rate of technological change or whether it can be explained by non-technological factors relating to factor utilization, factor accumulation, or returns to scale. It finds that the recent increase in productivity growth does appear to arise from an increase in technological change. Cyclical utilization raised measured productivity growth relative to technology growth in the first part of the expansion, but lowered it subsequently. Factor adjustment leads to a steady-state understatement of technology growth by measured productivity growth. The understatement was greater in the second half of the expansion than the first. Changes in the distribution of inputs across industries with different returns to scale lead to a modest understatement in the growth in technology. Although the increase technological change is most pronounced in durable manufacturing, technological change also increased outside of manufacturing.

Abstract:
Measured productivity growth increased substantially during the second half of the 1990s. This paper examines whether this increase owes to an increase in the rate of technological change or whether it can be explained by non-technological factors relating to factor utilization, factor accumulation, or returns to scale. It finds that the recent increase in productivity growth does appear to arise from an increase in technological change. Cyclical utilization raised measured productivity growth relative to technology growth in the first part of the expansion, but lowered it subsequently. Factor adjustment leads to a steady-state understatement of technology growth by measured productivity growth. The understatement was greater in the second half of the expansion than the first. Changes in the distribution of inputs across industries with different returns to scale lead to a modest understatement in the growth in technology. Although the increase technological change is most pronounced in durable manufacturing, technological change also increased outside of manufacturing.

Abstract:
The Fed kept interest rates low and essentially unchanged during the late 1990s despite a booming economy and record-low unemployment. These interest rates were accommodative by historical standards. Nonetheless, inflation remained low. How did the Fed succeed in sustaining rapid economic growth without fueling inflation and inflationary expectations? In retrospect, it is evident that the productive capacity of the economy increased. Yet as events unfolded, there was uncertainty about the expansion of the capacity of the economy and therefore about the sustainability of the Fed's policy.

This paper provides an explanation for the success of the Fed in accommodating noninflationary growth in the late 1990s. It shows that if the Fed is committed to reverse policy errors it makes because of unwarranted optimism, inflation can remain in check even if the Fed keeps interest rates low because of this optimism. In particular, a price level target - which is a simple way to model a commitment to offset errors - can serve to anchor inflation even if the public believes the Fed is overly optimistic about shifts in potential output. The paper shows that price level targeting is superior to inflation targeting in a wide range of situations. The paper also provides econometric evidence that, in contrast to earlier periods, the Fed has recently has put substantial weight on the price level in setting interest rates. Moreover, it shows that CPI announcement surprises lead to reversion in the price level. Finally, it provides textual evidence that Alan Greenspan puts relatively more weight on the price level than inflation.

Monetary policy, Taylor rule, uncertain potential output

Abstract:
This paper studies the efficiency with which physical capital can be reallocated across sectors. It presents a model of a firm selling specialized capital in a thin resale market. The model predicts that the selling price depends not only on the sectoral specificity of capital, but also on the thinness of the market and the discount factor of the firm. It then provides empirical evidence on the sectoral mobility of capital based on equipment-level data from aerospace industry auctions. These data track the flow of used capital across industries, as well as the discounts at which the capital sells. The results suggest substantial sectoral specificity of capital. Capital that flowed out of the sector sold for only one-third of its estimated replacement cost.

Abstract:
This paper studies the efficiency with which physical capital can be reallocated across sectors. It presents a model of a firm selling specialized capital in a thin resale market. The model predicts that the selling price depends not only on the sectoral specificity of capital, but also on the thinness of the market and the discount factor of the firm. It then provides empirical evidence on the sectoral mobility of capital based on equipment-level data from aerospace industry auctions. These data track the flow of used capital across industries, as well as the discounts at which the capital sells. The results suggest substantial sectoral specificity of capital. Capital that flowed out of the sector sold for only one-third of its estimated replacement cost.

Abstract:
In 2001, many households received rebate checks as advanced payments of the benefit of the new, 10 percent federal income tax bracket. A survey conducted at the time the rebates were mailed finds that few households said that the rebate led them mostly to increase spending. A follow-up survey in 2002, as well as a similar survey conducted after the attacks of 9/11, also indicates low spending rates. This paper investigates the robustness of these survey responses and assesses whether such surveys are useful for policy evaluation. It also draws lessons from the surveys for macroeconomic analysis of the tax rebate.

Abstract:
Many households received income tax rebates in 2001 of $300 or $600. These rebates represented advance payments of the tax cut from the new 10 percent tax bracket. Based on a survey of a representative sample of households, this paper finds that only 22 percent of households receiving the rebate would spend it. Instead, they would either save it or use it to pay off debt. This very low rate of spending represents a striking break with past behavior, which would have suggested a much higher rate of spending. The low spending rate implies that the tax rebate provided a very limited stimulus to aggregate demand.

Abstract:
The effect of Social Security rules on the age people choose to retire can be critical in evaluating proposed changes to those rules. This research derives a theory of retirement that views retirement as a special type of labor supply decision. This decision is driven by wealth and substitution effects on labor supply, interacting with a fixed cost of working that makes low hours of work unattractive.

The theory is tractable analytically, and therefore well-suited for analyzing proposals that affect Social Security. This research examines how retirement age varies with generosity of Social Security benefits. A ten-percent reduction in the value of benefits would lead individuals to postpone retirement by between one-tenth and one-half a year. Individuals who are relatively buffered from the change¿because they are wealthier or because they are younger and therefore can more easily increase saving to offset the cut in benefits¿will have smaller changes in their retirement ages.

Abstract:
No abstract is available for this paper.

Abstract:
A number of analysts have claimed recently that the consumer price index overstates the annual increase in the cost of living. This paper develops a framework for studying measurement problems in the consumer price index and systematically analyzes the available evidence concerning the magnitude of these problems. It concludes that the CPI overstates increases in the cost of living. The evidence suggests that the bias is centered on 1.0 percentage point per year. The extent of this bias is not known exactly. To take into account this uncertainty, the estimated bias is presented in terms of a probability distribution rather than a point estimate or range. We estimate that there is a 10 percent chance that the bias is less than 0.6 percentage point and a 10 percent chance that it is greater than 1.5 percentage points per year. CPI procedures overstate the rate of inflation for medical procedures that are subject to technological improvement. To illustrate this point and to show how better to measure medical care prices, the paper presents a prototypical price index for cataract surgery. This price index grows much more slowly than a price index for cataract surgery constructed using the methodology of the CPI. The paper discusses implications of CPI mismeasurement for monetary and fiscal policy as well as for other official statistics. It also offers some suggestions for improving the CPI.

Abstract:
A number of analysts have claimed recently that the consumer price index overstates the annual increase in the cost of living. This paper develops a framework for studying measurement problems in the consumer price index and systematically analyzes the available evidence concerning the magnitude of these problems. It concludes that the CPI overstates increases in the cost of living. The evidence suggests that the bias is centered on 1.0 percentage point per year. The extent of this bias is not known exactly. To take into account this uncertainty, the estimated bias is presented in terms of a probability distribution rather than a point estimate or range. We estimate that there is a 10 percent chance that the bias is less than 0.6 percentage point and a 10 percent chance that it is greater than 1.5 percentage points per year. CPI procedures overstate the rate of inflation for medical procedures that are subject to technological improvement. To illustrate this point and to show how better to measure medical care prices, the paper presents a prototypical price index for cataract surgery. This price index grows much more slowly than a price index for cataract surgery constructed using the methodology of the CPI. The paper discusses implications of CPI mismeasurement for monetary and fiscal policy as well as for other official statistics. It also offers some suggestions for improving the CPI.

Abstract:
This paper shows how to generate the joint distribution of correlated random variables with specified marginal distributions. For cases where the marginal distributions are either normal or lognormal, it shows how to calculate analytically the correlation of the underlying normal distributions to induce the desired correlation between the variables. It also provides a method for calculating the joint distribution in the case of arbitrary marginal distributions. The paper applies the technique to calculating the distribution of the overall bias in the consumer price index. The technique should also be applicable to estimation by simulated moments or simulated likelihoods and to Monte Carlo analysis.

Abstract:
Changes in government spending often lead to significant shifts in demand across sectors. This paper analyzes the effects of sector-specific changes in government spending in a two-sector dynamic general equilibrium model in which the reallocation of capital across sectors is costly. The two-sector model leads to a richer array of possible responses of aggregate variables than the one-sector model. The empirical part of the paper estimates the effects of military buildups on a variety of macroeconomic variables using a new measure of military shocks. The behavior of macroeconomic aggregates is consistent with the predictions of a multi-sector neoclassical model. In particular, consumption, real product wages and manufacturing productivity fall in response to exogenous military buildups in the post-World War II United States.

Abstract:
Individuals' preferences underlying most economic behavior are likely to display substantial heterogeneity. This paper reports on direct measures of preference parameters relating to risk tolerance, time preference, and intertemporal substitution. These experimental measures are based on survey respondents' choices in hypothetical situations. The questions are constructed with as little departure from the theorist's concept of the underlying parameter as possible. The individual measures of preference parameters display substantial heterogeneity. The majority of respondents fall into the least risk-tolerant group, but a substantial minority display higher risk tolerance. The individual measures of intertemporal substitution and time preference also display substantial heterogeneity. The mean risk tolerance is 0.25; the mean elasticity of intertemporal substitution is 0.2. Estimated risk tolerance and the elasticity of intertemporal substitution are essentially uncorrelated across individuals. Because the risk tolerance measure is obtained as part of the main questionnaire of a large survey, it can be related to a number of economic behaviors. Measured risk tolerance is positively related to a number of risky behaviors, including smoking, drinking, failing to have insurance, and holding stocks rather than Treasury bills. Although measured risk tolerance explains only a small fraction of the variation of the studied behaviors, these estimates provide evidence about the validity and usefulness of the measures of preference parameters.

Abstract:
Investment decisions are inherently forward-looking. The payoff of acquiring capital goods, particularly long-lived capital goods, is governed almost exclusively by events in the far future. Because the timing of the investment itself does not affect future payoffs, there are strong incentives to delay or accelerate investment to take advantage of predictable intertemporal variations in cost. For sufficiently long-lived capital goods, these incentives are so strong that the intertemporal elasticity of investment demand is nearly infinite. As a consequence, for a temporary tax change, the shadow price of long-lived capital goods must reflect the full tax subsidy regardless of the elasticity of investment supply. While price data provide no information on the elasticity of supply, they can reveal the extent to which adjustment costs are internal or external to the firm. In contrast, the elasticity of investment supply can be inferred from quantity data alone. The bonus depreciation allowance passed in 2002 and increased in 2003 presents an opportunity to test the sharp predictions of neoclassical investment theory. In the law, certain types of long-lived capital goods qualify for substantial tax subsides while others do not. The data show that investment in qualified properties was substantially higher than for unqualified property. The estimated elasticity of investment supply is high--between 10 and 20. Market prices do not react to the subsidy as the theory dictates. This suggests either that internal (unmeasured) adjustment costs play a significant role or that measurement problems in the price data effectively conceal the price changes. While the policy noticeably increased investment in types of capital that benefited substantially from bonus depreciation, the aggregate effects of the policy were modest. The analysis suggests that the policy may have increased output by roughly 0.1 percent to 0.2 percent and increased employment by roughly 100,000 to 200,000 jobs.

Abstract:
The value of installed computers falls rapidly and therefore computers have a very high user cost. The paper provides a complete account of the non-financial user cost of personal computers -- decomposing it into replacement cost change, obsolescence, instantaneous depreciation, and age-related depreciation. The paper uses data on the resale price of computers and a hedonic price index for new computers to achieve this decomposition. Once obsolescence is taken into account, age-related depreciation -- which is often identified as deterioration -- is estimated to be negligible. While the majority of the loss in value of used computers comes from declines in replacement cost, this paper shows the second most important source of decline in value is obsolescence. Obsolescence is accelerated by the decline in replacement cost of computers. Cheaper computing power drives developments in software and networks that make older computers less productive even though their original functionality remains intact.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
The interaction between the macroeconomy and asset markets is central to a variety of modern theories of the business cycle. Much recentwork emphasizes the joint nature of the consumption decision and the portfolio allocation decision. In this paper, we compare two formulations of the Capital Asset Pricing Model. The traditional CAPM suggests that the appropriate measure of an asset`s risk is the covariance of the asset`s return with the market return. The consumption CAPM, on the other hand, implies that a better measure of risk is the covariance with aggregate consumption growth. We examine a cross section of 464 stocks and find that the beta measured with respect to a stock market index outperforms the beta measured with respect to consumption growth.

Abstract:
Only one-fifth of respondents to a rider on the University of Michigan Survey Research Center's Monthly Survey said that the 2008 tax rebates would lead them to mostly increase spending. Almost half said the rebate would mostly lead them to pay off debt, while about a third saying it would lead them mostly to save more. The survey responses imply that the aggregate propensity to spend from the rebate was about one-third, and that there would not be substantially more spending as a lagged effect of the rebates. Because of the low spending propensity, the rebates in 2008 provided low "bang for the buck" as economic stimulus. Putting cash into the hands of the consumers who use it to save or pay off debt boosts their well-being, but it does not necessarily make them spend. Low-income individuals were particularly likely to use the rebate to pay off debt.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
Economic theory assigns a central role to risk preferences. This paper develops a measure of relative risk tolerance using responses to hypothetical income gambles in the Health and Retirement Study. In contrast to most survey measures that produce an ordinal metric, this paper shows how to construct a cardinal proxy for the risk tolerance of each survey respondent. The paper also shows how to account for measurement error in estimating this proxy and how to obtain consistent regression estimates despite the measurement error. The risk tolerance proxy is shown to explain differences in asset allocation across households.

Abstract:
Labor supply is unresponsive to permanent changes in wage rates. Thus, income and substitution effects cancel, but are they both close to zero or both large? This paper develops a theory of labor supply where income and substitution effects cancel, taking into account optimization over time, fixed costs of going to work, and interactions of labor supply decisions within the household. The paper then applies this theory to survey evidence on the response of labor supply to a large wealth shock. The evidence implies that the constant marginal utility of wealth (Frisch) elasticity of labor supply is about one.

Abstract:
The durability of health care treatment, the substantial technical change in health care treatment, and the prevalence of third-party payment interact to create substantial difficulty in measuring the price and output of health care. This paper provides a framework for analyzing the demand for health care taking into account these difficulties. It then suggests how this framework might be used to improve measurement of health care prices and output.

Abstract:
No abstract is available for this paper.

Abstract:

Abstract:
Phased-in tax reductions are a common feature of tax legislation. This paper uses a dynamic general equilibrium model to quantify the effects of delaying tax cuts. According to the analysis of the model, the phased-in tax cuts of the 2001 tax law substantially reduced employment, output, and investment during the phase-in period. In contrast, the immediate tax cuts of the 2003 tax law provided significant incentives for immediate production and investment. The paper argues that the rules and accounting procedures used by Congress for formulating tax policy have a significant impact in shaping the details of tax policy and led to the phase-ins, sunsets, and temporary tax changes in both the 2001 and 2003 tax laws.

Abstract:
We examine the small sample properties of tests of rational expectations models. We show using Monte Carlo experiments that the asymptotic distribution of test statistics can be extremely misleading when the tine series examined are highly autoregressive. In particular, a practitioner relying on the asymptotic distribution will reject true models too frequently. We also show that this problem is especially severe with detrended data. We present correct small sample critical values for our canonical problem.

Abstract:
The Fed kept interest rates low and essentially unchanged during the late 1990s despite a booming economy and record-low unemployment. These interest rates were accommodative by historical standards. Nonetheless, inflation remained low. How did the Fed succeed in sustaining rapid economic growth without fueling inflation and inflationary expectations? In retrospect, it is evident that the productive capacity of the economy increased. Yet as events unfolded, there was uncertainty about the expansion of the capacity of the economy and therefore about the sustainability of the Fed's policy.

This paper provides an explanation for the success of the Fed in accommodating growth with stable inflation in the late 1990s. It shows that if the central bank is committed to reverse policy errors it makes because of unwarranted optimism, inflation can remain in check even if the central bank keeps interest rates low because of this optimism. In particular, a price level target — which is a simple way to model a commitment to offset errors — can serve to anchor inflation even if the public does not share the central bank's optimism about shifts in potential output. The paper shows that price level targeting is superior to inflation targeting in a wide range of situations. The paper also provides econometric evidence that, in contrast to earlier periods, the Fed has recently put substantial weight on the price level in setting interest rates. Moreover, it shows that CPI announcement surprises lead to reversion in the price level. Finally, it provides textual evidence that Alan Greenspan puts relatively more weight on the price level than inflation.

Abstract:
No abstract is available for this paper.

Abstract:
The Consumer Price Index does not take into account the fact that consumers alter the composition of their purchases in response to changes in relative prices. This substitution effect will cause the CPI to grow faster than the cost of living. This paper presents new estimates showing that this bias in the CPI averaged 0.3 percentage points per year between December 1986 and December 1995. This bias could be eliminated by using a superlative index to aggregate prices across the item-area strata of the CPI. The paper discusses the practical difficulties in implementing such a calculation and suggests a method for overcoming them. In particular, it shows how to construct an accurate approximation to a superlative price index that can be published with the same timeliness as the CPI.

Abstract:
Measured productivity is strongly procyclical. Real business cycle theories suggest that actual fluctuations in productivity are the source of fluctuations in aggregate output. Keynesian theories maintain that fluctuations in aggregate output come from shocks to aggregate demand. Keynesian theories appeal to labor hoarding or off the production function behavior to explain the procyclicality of productivity. If observed productivity shocks are true productivity shocks, a function of factor prices should covary exactly with productivity. In annual data for U.S. industries, that function of factor prices and conventionally-measured productivity move together very closely. Moreover, their difference is uncorrelated with aggregate output.

Abstract:
This paper investigates the use of high-frequency scanner data to construct price indexes. In the presence of inventory behavior, purchases and consumption by individuals differ over time. Cost-of-living indexes can still be constructed using data on purchases. For weekly data on canned tuna, the paper contrast two different types of price indexes: fixed-base and chained indexes. Only the former are theoretically correct, and in fact, the chained indexes have a pronounced upward bias for most regions of the U.S. This upward bias can be caused by consumers purchasing goods for inventory. The paper presents some direct statistical support for inventory behavior being the cause of the upward bias, though advertising and special displays also have a very significant impact on shopping patterns.

Abstract:
Survey measures of preference parameters provide a means for accounting for otherwise unobserved heterogeneity.This paper presents measures of relative risk tolerance based on responses to survey questions about hypothetical gambles over lifetime income.It discusses how to impute estimates of utility function parameters from the survey responses using a statistical model that accounts for survey response error. There is substantial heterogeneity in true preference parameters even after survey response error is taken into account.The paper discusses how to use the preference parameters imputed from the survey responses in regression models as a control for differences in preferences across individuals. This paper focuses on imputations for respondents in the Panel Study of Income Dynamics (PSID).It also studies the covariation of risk preferences among members of households.It finds fairly strong covariation in attitudes about risk -- between parents and children and especially between siblings and between spouses.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
This paper studies the nature of the errors in preliminary GNP data, It first documents that these errors are large. For example, suppose the prelimimary estimate indicates that real GNP did not change over the recent quarter; then one can be only 80 percent confident that the final estimate (annual rate) will be in the range from -2.8 percent to +2.8 percent. The paper also documents that the revisions in GNP data are not forecastable, This finding implies that the preliminary estimates are the efficient given available information. Hence, the Bureau of Economic Analysis appears to follow efficient statistical procedures, in making its preliminary estimates.

Abstract:
No abstract is available for this paper.

Abstract:
Romer and Romer (1989, 1990, 1992) identify dates where the
Federal Reserve appears to have shifted its policy towards
reducing the rate of inflation. This paper examines the economic
context that drives this decision. It finds that the Fed appears
to weigh the outlook for unemployment as well as that for
inflation in making its decision about disinflation.

Previous work has not examined the course of inflation over the
disinflations. This paper finds responses of the inflation rate
to the "disinflations" only in a specification where the effects
of the policy are presumed to be permanent. Moreover, the
Volcker disinflation is found to be the only "disinflation"
to reduce inflation permanently. The disinflation after the
1973 OPEC increases was effective, but only temporarily. Other
disinflations had negligible impacts on the rate of inflation
over all horizons.

Variables measuring the expected present discounted values of
unemployment and inflation are constructed. These variables are
used in a discrete-choice model to explain the Fed's decision to
disinflate. This model does a fairly good job of explaining the
Fed's decisions. Both inflation and unemployment drive the Fed's
decision. For some episodes, notably in the 1970's, inflation
is the main variable driving the decision. In the 1969 and
1988 episodes, unemployment matters more.

Abstract:
No abstract is available for this paper.

Abstract:
Until recently, economists widely believed that economic activity had become less variable in the United States following the end of World War II. Challenging this belief, new research suggests that key historical time series are spuriously volatile, a finding that is highly controversial. Data from the stock market may provide a vehicle for resolving the controversy. Economic theory relates stock prices to real activity; empirical tests also show a strong link between stock prices and activity. Financial data are accurately measured over long spans of time and hence are free of most of the measurement problems in other time series. Measures of stock prices show no stabilization in the post-World War II period relative to the pre-World War I or pre-Depression periods. These stock market data thus support the hypothesis that real activity has not been stabilized.

Abstract:
Only about one-fifth of respondents in the Reuters/University of Michigan survey report that the 2008 tax rebates led them to mostly increase spending, while over half said it would lead them to mostly pay off debt. Of those in the mostly-spend category, the response was swift, with over 80 percent reporting increasing their spending within three months of receiving their rebate. Older households, households with higher wealth and higher income, and those expecting future income growth were generally more likely to spend the rebates. A review of other surveys confirms the general pattern of results and suggests that small changes in survey design do not have a major effect on the distribution of responses. The distribution of survey answers corresponds to an aggregate MPC after one year of about one-third. The paper combines this survey-based estimate of the MPC and the survey-based estimate of the timing of spending to show that the rebates help explain the aggregate movements in saving, spending, and debt in 2008. Because the rebate was large and distributed over a short period, it had a non-trivial effect on total spending in the second and third quarters of 2008. Nonetheless, the results imply that the rebates provided only a modest stimulus to spending per dollar of rebate.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
This paper emphasizes the role of wage growth in shaping work incentives. It provides an analytical framework for labor supply in the presence of a return to labor market experience and aggregate productivity growth. A key finding of the theory is that there is an interaction between these two forms of wage growth that explains why aggregate productivity growth can affect employment rates in steady state. The model thus speaks to an enduring puzzle in macroeconomics by uncovering a channel from the declines in trend aggregate wage growth that accompanied the productivity slowdown of the 1970s to persistent declines in employment.The paper also shows that the return to experience for high school dropouts has fallen substantially since the 1970s, which further contributes to the secular decline in employment rates. Taken together, the mechanisms identified in the paper can account for all of the increase in nonemployment among white male high school dropouts from 1968 to 2006. For all white males, it accounts for approximately one half of the increase in the aggregate nonemployment rate over the same period.

Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Abstract:
New Zealand's recent rate of economic growth has remained strong despite a worldwide recession. Policymakers, the press, and the public have nonetheless been concerned that New Zealand's economic performance has lagged along some important dimensions. This paper presents some new estimates of the rate of technological change in New Zealand and compares them to similar measures for the United States and elsewhere. New Zealand has not participated in the increased pace of technological progress seen elsewhere since the mid-1990s. Technological change creates sustainable increases in income and wages. Hence, it should be an important focus of policy discussions surrounding economic growth. The paper also addresses how public policy should take into account technological change, especially given uncertainty about future prospects for its growth and the difficulties of public policy in changing its growth.

Abstract:
Using equipment-level data from aerospace plants that closed during the 1990s, this paper studies the process of moving installed physical capital to a new use. The analysis yields three results that suggest significant sectoral specificity of physical capital and substantial costs of redeploying the capital. First, other aerospace companies are overrepresented among buyers of the used capital relative to their representation in the market for new investment goods. Second, even after age-related depreciation is taken into account, capital sells for a substantial discount relative to replacement cost; the more specialized the type of capital, the greater the discount. Yet, capital sold to other aerospace firms fetches a higher price than capital sold to industry outsiders. Finally, the process of winding down operations and selling the equipment takes several years.