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 share of U.S. workers in alternative work arrangements has increased substantially in recent decades. Micro longitudinal analyses show that unemployed workers are much more likely to transition into alternative work arrangements than other workers. Macro time-series evidence shows that weak labor market conditions lead to an increase in non-traditional work. But the estimated magnitudes imply that the Great Recession and high unemployment in the 2000s can account for only a modest part of the rise in alternative work. Secular factors associated with rising inequality and technological changes making it easier to contract out work appear to be the driving forces.

What Does Performance in Graduate School Predict? Graduate Economics Education and Student Outcomes by Susan Athey, Lawrence F. Katz, Alan B. Krueger, Steven Levitt and James Poterba. Published in volume 97, issue 2, pages 512-520 of American Economic Review, May 2007