Quote from FCCT:
Buying power is not an issue in this business...so percentage gain doesnt make sence...and your 500 day is equal to mine or anyones 500 day.
In the sense that i can take that 500 gain and buy the same things as you, correct. But in trading I would say otherwise. If my 500 gain was from a million dollar+ bond gain and yours was from gambling all of your account at once, it is not. I know those are two extremes, but that is the example of why percentage exists. it exists and is derived from risk...not buying power.
RT
EDIT: also, percentage is the only effective means of comparison between two seperate time frames. If you make $50,000 on your account this year, it is much easier to make $50,000 on that same account in the next year.