Completely wrong.
You have to fight first against participants. Only if you can make money you will have to fight against taxrates. Taxrates are a result of profit, and profit is a result from fighting against participants.
In US, of course, roughly 20% to 48% percent for the yearly profit. But above many traders has lot of commission. So I mean thinking about possible sucker who pay comm+tax more than his ProfitBeforeExpense.
There is good research paper, regarding percentage of winners in the long run.
http://faculty.haas.berkeley.edu/odean/Odean CV.pdf
“Just How Much Do
Investors Lose from Trade?” with Brad Barber, Yi-Tsung Lee and Yu-Jane Liu, Review of Financial Studies, 2009, Vol. 22, 2, 609-632.
“Does Online Trading Change Investor Behavior?” with Brad Barber, European Business Organization Law Review, 2002, Vol. 3, 83-128.
"The
Internet and the Investor" with Brad Barber, The Journal of Economic Perspectives, Winter 2001, Vol. 15, No. 1, pp. 41-54.
"Too Many Cooks Spoil the Profits: The Performance of Investment Clubs" with Brad Barber, Financial Analyst Journal, January/February 2000, 17-25.
"Are Investors
Reluctant to Realize Their Losses?", Journal of Finance, Vol. LIII, No. 5, October 1998, 1775-1798.