condition mean min max ZT0-3 27.450000000000003 27.450000000000003 27.450000000000003 ZT4-7 16.6 16.6 16.6 ZT8-11 23.4 23.4 23.4 ZT12-15 34.400000000000006 34.400000000000006 34.400000000000006 ZT16-19 22.15 22.15 22.15 ZT20-23 23.6 23.6 23.6