Seven hundred years of climatic information gathered from tree rings shows that, on average, the U.S. has experienced a major drought every 18 or 19 years.

The longest span between droughts is 23 years. Given these facts, Iowa State University climatologist Elwynn Taylor told attendees at the National Ag Bankers conference earlier this month that the Midwest is due for a drought. The last major drought was 1988— 18 years ago—so the odds for a drought grow significantly stronger each year.