condition mean min max ZT0-3 3.9688 3.0835150000000002 4.4133949999999995 ZT4-7 2.639925 2.639925 2.639925 ZT8-11 1.78986 1.78986 1.78986 ZT12-15 2.9500425 2.466775 3.4333099999999996 ZT16-19 3.172295 3.172295 3.172295 ZT20-23 4.294165 4.294165 4.294165