The Meat Grinder Of War – Why The Napoleonic Wars Cost So Many Lives
Andrew Knighton

"The Napoleonic Wars involved staggering numbers of men injured and killed. From 6% casualties at Fleurus in 1792 to 15% at Austerlitz in 1806. There were 31% at Eylau in 1807 and a terrifying 45% at Waterloo in 1815. The sheer number of men broken by the wars was horrifying. Some survived their injuries, although it is likely millions died. The 3.7 million deaths estimated by historian Hippolyte Taine may be an exaggeration, but it must be in the right area...."

https://www.warhistoryonline.com/napoleon/napoleonic-wars-cost-many-lives.html