 For every 100 females age 18 and over, there were 99.70 males.With a median household income of $67,400 (2008 estimate - $72,700) and a median family income of $75,284, Livingston County is one of the highest-income counties in the United States and has the second-highest median income in Michigan (after Oakland).Males had a median income of $54,358 versus $32,073 for females.