As Paul said, teh IAQ measures in tenths of a degree, and will bring on your A/C before the temp rises to the next degree.
Not 100% how it works, just for reference.
Stat set at 72*F, temp reaches 72.5°F(still shows 72), stat runs A/C, temp reaches 71.9°F, stat turns off A/C(still shows 72).
Your CPH should not be set higher then 3 CPH for first stage.
You can also set it for a more aggressive cooling cycle. If you do, it may over shoot temp.
But your off cycles will be longer.
Check your first stage CPH first.