condition mean min max ZT0-3 16.080849999999998 15.9143 16.2474 ZT4-7 13.5249 13.5249 13.5249 ZT8-11 20.462600000000002 20.462600000000002 20.462600000000002 ZT12-15 0 0 0 ZT16-19 28.939349999999997 28.939349999999997 28.939349999999997 ZT20-23 18.7113 18.7113 18.7113