From July 1906 through June 1907 in Allegheny County, Pennsylvania, 526 workers died in "work accidents"; 195 of these were steelworkers.

That's how bad things used to be in the United States before a century of labor reform.

Data from multiple sources show America's worker fatality rate declining from 61 deaths per 100,000 workers in 1913 to 37 per 100,000 workers in 1933 to 4 per 100,000 workers in 1999.

We came across these figures in a CDC report while researching the most dangerous jobs in America today, which by contrast are extremely safe. There were only 4,693 fatal injuries in America in 2011 — less than nine times as many as there were in Allegheny County in that single year.

Dangerous work still happens every day, however, in Bangladeshi garment factories, Chinese coal mines, and other locations around the world.