Check your math. 100*(1,500,000/239,460,000) = 0.627%.
Just eyeballing it should tell you that 1 million is 1% of 100 million. So there's no way 1.5 million could be 6+% of 239 million.
And you should probably subtract children, retired people, and the disabled from the population to get a better overall number.
http://www.bls.gov/cps/
**The following calculation is only being used to determine the size of the US workforce, not to dispute the unemployment # you presented**
2010 #'s:
Unemployment rate = 9.1%
# of unemployed = 14,825,000
Total population of workforce should be about (14,825,000/.091) = 163 million.
So instead of using 307 million, try using 163 million.
1.5/163 = 0.92% of the US works at Wallyworld and Target.
Also note: "The labor force is the sum of employed and unemployed persons. The labor force participation rate is the labor force as a percent of the civilian noninstitutional population."
ftp://ftp.bls.gov/pub/special.requests/lf/aat3.txt