You created a portfolio 5 years ago. You invested 45% of your money in Stock A and 55% of your money in Stock B. For the past five years the annual returns on Stock A were: 20%, 18%, -15%, 15% and 23%. During the past five years the annual returns on Stock B were: -5%, 25%, 30%, 20%, and -10%. What was the average annual return on the portfolio?