Ten-pin bowling ball contacts only the 1, 3, 5 and 9 pins; for a left-hander, the 1, 2, 5 and 8 pins. In order to count, a pin must be knocked over entirely. If the pin is wobbling as the automatic pin machine picks it up (or the machine itself knocks over the pin while it is wobbling), it is still considered standing and is not scored. Also, if a pin is moved, it does not change its designation. For example, if the 10 pin were still standing and the 7 pin slid into the 8 pin position, converting this spare would
Ten-pin bowling have a decimal component (numbers to the right of the decimal point) discard all numbers to the right of the decimal point, leaving only a whole number, as rounding any decimal number equal or higher than 0.500, "up" to the next highest whole number when calculating averages is prohibited by USBC rules on scoring in tenpins. As of the 2014–15 season, approximately 1.57 million people compete in bowling leagues in the United States. At its peak in 1980, over eight million men and women competed in leagues throughout the United States. In ten-pin bowling there are two major world organizations