Posts have nothing to do with it as far as I know. You always rep for 0.5% of your own reputation, approximated to units by defect(?). Which means, if 0.5% of your reputation is 4.9, it approximates to 4 instead of 5.
Right now your reputation is 201. 0.5% of that is 1.005, which equals +1 every reputation gift.
To easily find out the «power» of your reputation gift, divide your own reputation by 100, then divide again by 2. The resulting value of those divisions is the «power» of your reputation gift.
The only case of exception is to people who haven't yet made it to 200 reputation, they'll give +1 regardless, if I'm not wrong.