What must the annual percentage rate (APR) of a loan be expressed as?

The annual percentage rate (APR) of a loan must be expressed as the effective interest rate. The effective interest rate takes into account the impact of compounding over the year and conveys the true cost of borrowing on an annual basis. It provides borrowers with an understanding of the overall expense they will incur when taking out the loan, including not just the nominal interest rate, but also fees and additional costs associated with the loan product.

This expression is crucial as it helps standardize the presentation of loan costs across various lenders and financial products, allowing consumers to make informed comparisons. Therefore, representing the APR as the effective interest rate aligns with the objectives of the Truth in Lending Act, which aims to provide transparent and clear information about loan terms to consumers.