As suggested by Darkhorse, it is important to normalize return for risk. Two traders may create the same amount of wealth, but it is important to know how wild the ride was getting to that point. There are numerous equity-based and trade-based statistics used to evaluate performance. However, in direct answer to the original question that started this thread, % profit is calculated as follows: $ profit / $ equity committed to the trade ($50/$500 = 10%). By including risk factors such as leverage, we would create a statistic other than % profit.