Returns earned over a given time period are called realized returns. Historical data on realized returns is often used to estimate future results. Analysts across companies use realized stock returns to estimate the risk of a stock. Consider the case of Happy Dog Soap Inc. (HDS): Five years of realized returns for HDS are given in the following table. Remember: 1. While HDS was started 40 years ago, its common stock has been publicly traded for the past 25 years. 2. The returns on its equity are calculated as arithmetic returns 3. The historical returns for HDS for 2012 to 2015 are: 2012 2013 2014 2015 2016 Stock return 21.25% 14.45% 25.50% 35.70% 11.05% Given the preceding data, the average realized return on HDS's stock is of HDS's historical returns. Based on this conclusion, the The preceding data series represents standard deviation of HDS's historical returns is