Over the past century (1916 to 2007), the frequency of extreme and exceptional droughts in Illinois and Indiana decreased. Exceptional droughts are the most severe form of drought experienced in the region, and extreme droughts are the second most severe. Until the recent drought of 2012, all of the exceptional droughts were prior to 1970, and the majority of them occurred during the dust bowl era of the 1930s. In general, more recent drought events have been less intense in their severity, duration, and spatial extent compared to earlier in the 20th Century. However, the 1988 drought was the fifth-driest year on record in the state of Illinois, which led to severe water shortages throughout the state. In addition, the 2012 drought was the most extensive drought on record across the U.S. since 1956. Changes in precipitation coupled with warmer temperatures will also likely lead to changes in drought characteristics, such as intensity, duration, frequency, and spatial extent. One study suggests that extreme and exceptional droughts in Illinois and Indiana may increase in duration, frequency, and spatial extent compared to the last 30 years of the 20th century. These findings are consistent with a global-scale study that found a projected increase in drought frequency, duration, and severity across the central U.S.