The 2011 GEM report is based on a survey of 140, 000 adults in 54 economies, including 6, 000 just in the U.S. Researchers looked at responses from a random samplingof participants, as well as population data for each of the countries represented, to draw conclusions about entrepreneurial activity in those nations.
If it used these sampling methods, the Census Bureau says, there is a 90% chance that its estimate of America's population would be within 0.1% of the true number.