According to the “Findings” in The Lancet study “Mortality after the 2003 invasion of Iraq: a cross-sectional cluster sample survey” from Oct. 12, 2006: “…We estimate that as of July, 2006, there have been 654[,]965 (392[,]979–942[,]636) excess Iraqi deaths as a consequence of the war, which corresponds to 2·5% of the population in the study area. Of post-invasion deaths, 601[,]027 (426[,]369–793[,]663) were due to violence, the most common cause being gunfire.”
– The Lancet, “Mortality after the 2003 invasion of Iraq: a cross-sectional cluster sample survey,” TheLancet.com, Oct. 12, 2006