I spent today reviewing my performance from late August 2012 and actually discovered that my return on equity is currently 11.32%, and not 7% as I initially assumed. Calculating your return on equity can be distorted if you're routinely depositing money. If you're continually adding money, then the magnitude of your earlier wins diminish compared to your more-recent wins. To make them comparable, you need to standardise your wins and losses throughout the review period. This will allow you to calculate an accurate return on equity.