I'll just leave this here...I'm not baiting or anything, I swear. Ahem.
Race and IQ: A Theory-Based Review of the Research in Richard Nisbett’s
Intelligence and How to Get ItJ. Philippe Rushton and Arthur R. Jensen
http://benthamopen.com/contents/pdf/TOPSYJ/TOPSYJ-3-9.pdf"Starting with the widespread use of standardized mental tests in the U.S. during World War I (1917), average ethnic and racial group differences have been found. Especially vexing has been the cause(s) of the 15- to 18-point IQ difference (1.0 to 1.1 standard deviations, SDs) between Blacks and Whites."
(p. 9)...
"Currently, the magnitude of the U.S. Black-White IQ difference is not in itself a major cause of scientific dispute. A recent meta-analytic review by Roth et al. [9] yielded a 1.1 SD difference (range = 0.38 to 1.46) for a total of 6,246,729 testees from corporate, military, and higher education samples."
(p. 10)...
"An IQ of 71 was found for the Black children in an entire school district from a rural county in Georgia in the U. S. Deep South; the White IQ in the same county was 101 [30]."