Michigan's Population Continues to Grow Dec. 22, 2005 - The U.S. Census Bureau today released new population estimates for all 50 states, Puerto Rico and the District of Columbia. Michigan's estimated population for July 2005 is 10,120,860, which is 0.2 percent higher than the newly revised 2004 figure of 10,104,206. Since the 2000 Census, Michigan's estimated population has increased by 1.8 percent, or 182,380 people.