condition mean min max ZT0-3 17.539433333333335 11.96605 22.824550000000002 ZT4-7 14.556049999999999 14.556049999999999 14.556049999999999 ZT8-11 14.780850000000001 14.780850000000001 14.780850000000001 ZT12-15 33.32435 29.69175 36.956950000000006 ZT16-19 32.71285 32.71285 32.71285 ZT20-23 32.5339 32.5339 32.5339