condition mean min max ZT0-3 5.377295 3.22677 7.52782 ZT4-7 11.472864999999999 11.472864999999999 11.472864999999999 ZT8-11 8.085484999999998 8.085484999999998 8.085484999999998 ZT12-15 0 0 0 ZT16-19 3.965455 3.965455 3.965455 ZT20-23 7.2621199999999995 7.2621199999999995 7.2621199999999995