Premise: Jefferson County is a county located in the U.S. state of Kentucky. As of the 2010 census, the population was 741,096. It is the most populous county in Kentucky and is more than twice as large as the second most populous, Fayette. The county was formed in 1780 and named for future President Thomas Jefferson, who was Governor of Virginia at the time.
Hypothesis: Jefferson County's population in 1780 was 200,000.