1969: a 29 year old man in the shipping department of a major Japanese nrewspaper dies of a stroke. This is the first case of karoshi or death by overwork, though it won’t be called that until a 1982 book by the same name.

2002: 819 people apply for compensation after family members died from karoshi. Estimates range from 1,000 to 10,000 deaths per year are related to working too hard—stroke, heart attack, cerebral hemorrhaging, even suicides are attributed to too much slogging.

If you are working more than 80 hours in overtime every month, you’re at a high risk for karoshi. So watch out for those 60 hour work weeks, friends, they are a killer.