Your portfolio consists of $100,000 invested in a stock which has a beta = 1.5, $150,000 invested in a stock which has a beta = 0.8, and $50,000 invested in a stock which has a beta = 2.1. The risk-free rate is 3 percent. Last year this portfolio had a required rate of return of 13 percent. This year nothing has changed except for the fact that the market risk premium has increased by 2% (This year market risk premium = Last year market risk premium + 2%). What is the portfolio's current year required rate of return? (Please write down the detailed formula and calculation process.)