The new analysis, which will be published in the February issue of the Annals of Epidemiology, included all 1,282,074 veterans who served in active-duty units between 2001 and 2007 and left the military during that period.

The analysis matched military records with the National Death Index, which collects data on every U.S. death. It tracked the veterans after service until the end of the 2009, finding a total of 1,868 suicides.

That equates to an annual suicide rate of 29.5 per 100,000 veterans, or roughly 50% higher than the rate among other civilians with similar demographic characteristics.