A friend sends along the following chart from a J.P. Morgan research report. It examines the prior private sector experience of the cabinet officials since 1900 that one might expect a president to turn to in seeking advice about helping the economy. It includes secretaries of State, Commerce, Treasury, Agriculture, Interior, Labor, Transportation, Energy, and Housing & Urban Development, and excludes Postmaster General, Navy, War, Health, Education & Welfare, Veterans Affairs, and Homeland Security—432 cabinet members in all.
When one considers that public sector employment has ranged since the 1950s at between 15 percent and 19 percent of the population, the makeup of the current cabinet—over 90 percent of its prior experience was in the public sector—is remarkable.
UPDATE: Politifact has raised some issues with the chart, which you can read about here.