Im saying that PG.Timer.DesiredFPS is the value that you set when PG.Timer.Init was called. Since aElapsedTime will always be a quantity associated with DesiredFPS then if you multiple aElapsedTime by 1.0 it will normalize it one second in this case. When the accumulated value become greater than PG.Timer.DesiredFPS (35) then one second of time has passed. If you wanted to check for 1/2 second then yes it would be 1/2 that (17.5).