Why do I shoot enemies in the left arm most of the time?

Here are my Counter Strike 1.6 rankstats for a certain period of play:

Kills : 971 (309 with hs)
Hits  : 3727
Shots : 17387
Acc.  : 21.43%

HITS      :
head      :  424 (11.95%)
chest     :  607 (17.10%)
stomach   :  406 (11.44%)
leftarm   : 1214 (34.21%)
rightarm  :  420 (11.83%)
leftleg   :  223 ( 6.28%)
rightleg  :  255 ( 7.19%)

Notice the very high percentage of shots aimed at the enemy's left arm. When shooting, I normally aim for the chest hoping for a headshot on the second or third fire but too may shots on left arm is unexplainable. Do I need to change my crosshair settings? Or should I aim a little towards right?