The following guest commentary was written in recognition of National Slavery and Human Trafficking Prevention Month.

Twenty-seven million. That is the number of people experts estimate are currently enslaved around the world. I first heard that number during my junior year of high school, when I began reading in Nicholas Kristof’s The New York Times column about the atrocious human rights abuses perpetrated against those millions of slaves, a phenomenon also known as human trafficking.

But 27 million is not an easy number to conceptualize – how many is that, really? Twenty-seven million people would fill Kinnick Stadium for every home game for the next 50 seasons of college football. Twenty-seven million people are more than the combined populations of Iowa, Minnesota, Wisconsin, Nebraska, Missouri and Kansas.