Contagious: Why Things Catch On

by Jonah Berger

simple way to figure out which discount frame seems larger is by using something called the Rule of 100. If the product’s price is less than $100, the Rule of 100 says that percentage discounts will seem larger. For a $30 T-shirt or a $15 entrée, even a $3 discount is still a relatively small number. But percentagewise (10 percent or 20 percent), that same discount looks much bigger. If the product’s price is more than $100, the opposite is true. Numerical discounts will seem larger. Take a $750 vacation package or the $2,000 laptop. While a 10 percent discount may seem like a relatively small number, it immediately seems much bigger when translated into dollars ($75 or $200). So when deciding how good a promotional offer really is, or how to frame a promotional offer to make it better, use the Rule of 100. Think about where the price falls relative to $100 and how that shifts whether absolute or relative discounts seem more attractive.