With fixed costs of participating in the stock market, consumers with high income will participate in the stock market, but consumers with lower income will not participate. If a fully funded defined-contribution Social Security system tries to exploit the equity premium by selling a dollar of bonds per capita and buying a dollar of equity per capita, consumers who save but do not participate in the stock market will increase their consumption, thereby reducing saving and capital accumulation. Calibration of a general-equilibrium model indicates that this policy could reduce the aggregate capital stock substantially, by about 50 cents per capita.

A straightforward generalization of the simple net present value rule that correctly predicts when to invest in two classes of projects that can be delayed is derived. The first class consists of projects for which the option to delay derives its value exclusively from uncertainty about interest rates. It is shown that the optimal rule for investing in such projects is to simply multiply the discount rate of the project by the ratio of the mortgage rate to the riskless rate and then use this new rate as the discount rate in a standard net present value analysis. The other class of investment opportunities that is considered is the firm's option to expand. It is shown that it is only optimal for the firm to expand when a particular call option on the firm's stock has no time value. The fact that mortgage bonds (in the form of GNMAs) and stock options are actively traded implies that these rules have potentially important practical and empirical value. Besides their simplicity, the rules have the added advantage that they do not depend on a maintained assumption on the dynamics of interest rates in the economy.

This paper considers conceptual and practical issues that arise in measuring labor's share of national income. Most importantly: How are workers defined? How is compensation defined? The current definition of labor compensation used the Bureau of Economic Analysis (BEA) includes the salary of business owners and payments to retired workers in labor compensation. An alternative series to the BEA's standard series is presented. In addition, a simple method for decomposing labor compensation into a component due to raw labor' and a component due to human capital is presented. Raw labor's share of national income is estimated using Census and CPS data. The share of national income attributable to raw labor increased from 9.6 percent to 13 percent between 1939 and 1959, remained at 12-13 percent between 1959 and 1979, and fell to 5 percent by 1996.

The defaults of U.S. States in the 1840's provide a powerful test of competing models of sovereign debt. The Eleventh Amendment to the United States Constitution prevented foreign creditors from obtaining payment in the federal courts. Moreover, because the defaulting states were part of a large and economically integrated nation, creditors could not enforce payment by imposing military or trade sanctions. In spite of the lack of sanctions, however, most states eventually repaid in full. It appears that the states repaid in order to maintain access to capital markets, much as in reputational models of sovereign debt.