5Y Avg Return on Equity is the average of the annual ROE number over the previous 5 financial years.

ROE helps understand number of units of profit generated per unit of money invested in the company. Higher the number better the utilisation of equity capital.

When analysing 2 or more companies, comparing ROE numbers for a single year will not suffice. It is possible that profits have increased or decreased substantially due to extraordinary profits or losses in a particular year, thereby falsifying the picture. Suppose we are comparing 5 years of data for 3 companies, we will have to inspect 15 (3*5) data points which can be cumbersome.

Instead, using average ROE is more simpler as well as eliminates the possibility of data distortion due to one-off earnings or losses.