condition mean min max ZT0-3 2.4270233333333335 1.82375 3.4217 ZT4-7 4.28609 4.28609 4.28609 ZT8-11 7.43703 7.43703 7.43703 ZT12-15 5.5572375 3.228325 7.886150000000001 ZT16-19 2.3025 2.3025 2.3025 ZT20-23 1.6105399999999999 1.6105399999999999 1.6105399999999999