The authors conducted a field experiment at a national chain of payday stores to examine the effectiveness of mandated disclosure with the goal of helping payday-loans borrowers overcome cognitive biases or limitations. Chief among these is a common failure to appreciate the true annualized interest rate of the loans, which run in several thousand percent. The disclosure information they provide includes annualized rates of interest, credit-card comparisons and peer usage statistics. They find that information that showing the adding-up effect of loan fees over several pay-cycles helps people think less narrowly about finance costs and results in 11% less borrowing in the subsequent 4 months.