Your swingspeed is the speed in mph that is reached at impact with the golf ball.  The number submitted should be your average swingspeed.  If you do not know your swingspeed you can estimate it by using the distance that you hit your 7 iron.  For instance if you hit your 7 iron 150yards, your swingspeed is 100.  For every 5 yards less or more, add or subtract 5 mph from 100.  So if you hit your 7 iron 140 yards, your swingspeed is 90.