What is a 'Stated Annual Interest Rate'
A stated annual interest rate is the return on an investment that is expressed as a peryear percentage, and that does not account for compounding that occurs throughout the year. The effective annual interest rate, on the other hand, does account for intrayear compounding that can occur on a daily, monthly or quarterly basis. Typically, the effective annual interest rate will lead to higher returns than the stated annual interest rate due to the power of compounding. Investors can compare products and calculate which type of interest will offer the most favorable return.
BREAKING DOWN 'Stated Annual Interest Rate'
A $10,000, oneyear certificate of deposit with a stated annual interest rate of 10% will earn $1,000 at maturity. If the money was placed in an interestearning savings account that paid 10% compounded monthly, the account will earn interest at a rate of 0.833% each month (10% divided by 12 months; 10/12 = 0.833). Over the course of the year, this account will earn $1,047.13 in interest, at an effective annual interest rate of 10.47%, which is notably higher than the returns on the 10% stated annual interest rate of the certificate of deposit used in the example.

Effective Annual Interest Rate
Effective Annual Interest Rate is an investment's annual rate ... 
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Annual Percentage Yield  APY
The effective annual rate of return taking into account the effect ... 
Annualize
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