By John Dodge

By John Dodge

CHICAGO (CBS) — On average, 86 percent of American adults hold a high school diploma, but how does the Chicago area compare?

The City Of Chicago and Cook County are the only areas locally that fall below the national average. In Chicago, only 81 percent hold a high school education, based on 2013 U.S. Census data.

Suburban Cook helps raise the county-wide average to 84 percent.

Other counties:

DuPage County: 92.1 percent
McHenry County: 92.1 percent
Will County: 90.5 percent
Lake County, Ill.: 88.9 percent
Lake County, Indiana: 87 percent

(Credit: U.S. Census)

(Credit: U.S. Census)

The map above by the U.S. Census Bureau, using data from 2005-2009, shows the standards for each county in the United States.

Texas has the highest number of least-educated counties, with more than two-dozen reporting high school diploma rates below 65 percent.

The entire state of Wyoming reports an 88 percent rate, all above the national average.

Illinois reports about a dozen counties with high school diploma rates between 75 percent to 80 percent.