Real Interest Rate: The True Cost of Borrowing and the Real Return on Investment
When you see an interest rate on a bank advertisement or a mortgage contract, you are looking at the Nominal Interest Rate . However, this number can be deceptive. To understand the actual growth of your wealth or the true burden of your debt, you must look at the Real Interest Rate . The Fisher Equation: The Math Behind the Money The relationship between inflation and interest rates is famously captured by the Fisher Equation , named after economist Irving Fisher. It is a simple but powerful tool for any investor. The Formula: Real Interest Rate ≈ Nominal Interest Rate - Inflation Rate For example, if your savings account offers a 5% interest rate (Nominal), but the inflation rate is 6% (CPI), your Real Interest Rate is -1% . Despite having more "dollars" in your account, your purchasing power has actually decreased. Why Re...