condition mean min max ZT0-3 2.74214 2.74214 2.74214 ZT4-7 1.8182749999999999 1.8182749999999999 1.8182749999999999 ZT8-11 1.814315 1.814315 1.814315 ZT12-15 2.50468 2.50468 2.50468 ZT16-19 3.3775399999999998 3.3775399999999998 3.3775399999999998 ZT20-23 2.893485 2.893485 2.893485