Defining profitability without measuring the risk taken is cheating both your clients and yourself, no doubt to earn a bonus above the watermark. If your risking everything and making 2-5%, then you will blowup fairly soon and if not, your clients are wrong to reward you for such unreasonable returns relative to the risks. There were a few banks that started using "EVA" economic value-add for the FX traders. They attempted to measure their returns to the amount of capital they risked from the banks balance sheet vs just asking them to make xx Million dollars budget each year. The traders got smart over time and realized that they could join a different bank that would not use EVA and make more bonus. Be fair..