What are the odds that extreme weather will lead to a global food shock? The insurance giant Lloyd’s evaluated the risks in a recent study.

The report looked at “major,” “severe,” and “extreme” scenarios. The authors found that the “major” case would cost the world $3 trillion over a five-year period, which they estimated has a 2.3% chance of happening per year. Over a 30-year period, those odds equate to about a 50% probability of occurrence — assuming the risks are not increasing each year, which they are.