In the United States, the American Airgun Field Target Association (AAFTA) rules set a maximum rifle power of 20 ft·lbf (27 J) primarily to limit damage to targets — there are no laws limiting airgun power in the United States. Individual competition rules may impose limits on power and/or other criteria at the discretion of the local match director. The increased velocity of the pellets from these higher power rifles primarily reduces the effects of distance (pellet drop) and windage (time of flight determines wind effects) but the game is, otherwise, quite similar to that of Britain and other countries.