Graduation rates change every year, and the definition is not always exactly the same.

In the most recent federal survey of state graduation rates, published in October 2011, the data are correct as of 2009.

At that time, the average for all reporting states was 75.5% and the states with the highest graduation rates were:

Wisconsin (where 90.7% of students graduated in four years’ time);

Vermont, 89.6%

North Dakota, 87.4%

Iowa, 85.7%

New Jersey, 85.3%

New Hampshire, 84.3%

Missouri, 83.1%

Nebraska, 82.9%

Montana, 82.0%

South Dakota, 81.7%

Idaho, 80.6%

Pennsylvania, 80.5%

Kansas, 80.2%

Maryland, 80.1%

The states with the lowest rates were Nevada (56.3%), Mississippi (62%), and the District of Columbia (62.5%).

Now bear in mind that these are four-year graduation rates. Students who graduate in August are not counted; students who graduate in five years or more are not counted. Students who get a GED are not counted. If these groups were added in, the graduation rate goes way up.