Result of my trading system backtest using metastock

Result of my trading system backtest using metastock

here is the result of my trading system i am backtesting
what i do is run the system onto every security and get the % gain after my system went through them.
it's done in a bear to bull market from 1 Jan 2000 to 27 Apr 2006
after that i deleted all untraded stocks to the stock count seen here. My country has about 780 securities
comments please.

Winnings:
Average percent gain 23.39%
Standard Dev 24.18%

Total count 105



Losings:
Average percent gain -6.83%
Standard Dev 5.59%

Total count 87

Summary
Aveage percent gain 8.28%
Average Standard Dev 14.8830734
Total Count 192

Win/Lost count ratio 1.206896552
Percent gain/lost ratio 342.62%



* at first glance, the reward/risk(Percent gain/lost ratio) ratio looks good. i think the Standard Dev of the winnings is insanely high! that the one biggest thing i am uncomfortable with. doesnt look like the average profit of 23.39% is a real profit. Can someone with statical knowledge help me with it?

* are there any other considerations?

there are many securities and i shall give the average
average winning trades / losing trades = 1.3/1.5

average profit/average loss = 2.35 <== this result cannot really be accurate because when a stock has only no losses or no winners, the results come out as "N/A"


top 3 trades :
121%
104%
100%

bottom 3 trades:
-25%
-23%
-22%