Here are the nominal returns on stocks, bonds, and bills for the 1920s and 1930s. For each decade, calculate the standard deviation of returns for each asset class

Here are the nominal returns on stocks, bonds, and bills for the 1920s and 1930s. For each decade, calculate the standard deviation of returns for each asset class Nominal Returns (%) on Stocks, Bonds, and Bills 1920s 1930s Stocks Bonds Bills Stocks Bonds Bills -17.9 5.8 7.6 -28.3 4.7 2.4 11.6 12.7 7.0 -43.9 -5.3 1.1 30.6 3.5 4.7 -9.8 16.8 1.0 3.0 5.7 5.2 57.6 -0.1 0.3 27.0 6.4 4.1 4.4 10.0 0.2 28.3 5.7 4.1 44.0 5.0 0.2 9.5 7.8 3.3 32.3 7.5 0.2 33.1 8.9 3.1 -34.6 0.2 0.3 38.7 0.1 3.6 28.2 5.5 0.0 -14.5 3.4 4.7 2.9 5.5 0.0