In 2009, a mere 9,000 H-1Bs were received in the first month of H-1B processing. It would be 264 days before the H-1B cap was reached. In 2010, it took 300 days until the H-1B cap was reached. In 2011, there were 236 days between the April 1, 2011 cap opening and the November 23, 2011 cap being reached. Not coincidentally, the US employment rate from 2009-2011 ranged between eight and ten percent.
On the other hand, the H-1B cap was reached on the very first day in 2007, 2008, each year since 2013, mirroring the low unemployment rate.
The lack of H-1B petition filings in years when the unemployment rate is high is compelling evidence against the argument that internationally-trained workers are being used to displace American workers and lower US workers' salaries.
Why? Because if H-1B visa labor was being used primarily to lower US workers’ salaries, then H-1B filing numbers would not correlate with US unemployment rates. If anything, the reverse would happen because the incentive to reduce workers’ salaries is likely greater in a recessed economy, not less.