Problem
At the end of every year, you analyze the performance and rebalance your retirement portfolio. Last year your portfolio earned 27.5%, which was 25% more than short-term treasury bill yield, one of your performance benchmarks. Your portfolio was also characterized by a 30% standard deviation of returns, while the benchmark treasury securities had a variance of just 1%. Meanwhile, the S&P 500, another of your performance benchmarks, yielded 22.5% and had a standard deviation of returns of 20%.
What was the Sharpe ratio of your portfolio?