condition mean min max ZT0-3 21.239675000000002 19.75495 22.724400000000003 ZT4-7 22.468049999999998 22.468049999999998 22.468049999999998 ZT8-11 22.209049999999998 22.209049999999998 22.209049999999998 ZT12-15 0 0 0 ZT16-19 30.9135 30.9135 30.9135 ZT20-23 27.4359 27.4359 27.4359