In St. Charles County, which finished with a state-best index score of 30.04, the median income was $99,596, investment income was $31,023 and median home value was $350,660.

The median income in Worth County, two hours north of Kansas City, is $43,536 and the county’s investment income is $17,134, lower than the state median of $31,357. The county has a population ...

Missouri has 114 counties, the fifth-most among all states, nearly doubling that of California, ... By the time Missouri became a state in 1821, it had grown to 25 counties in nine years.

The wealthiest county in Missouri is St. Charles County, according to SmartAsset. The median income in the county near St. Louis is $99,596, and the median home value is $350,660.