APR vs APY in Python: Why Your Savings Rate and Your Interest Don't Match

A friend sent me a screenshot last month: a savings account advertising "4.50% APY" and, in smaller print, "4.40% interest rate". She wanted to know which number was the real one and why a bank would show two. Both are real. They measure different things, and the gap between them is just compounding. It's a nice little problem to model in Python... Weiterlesen: APR vs APY in Python: Why Your Savings Rate and Your Interest Don't M…