condition mean min max ZT0-3 21.5 21.5 21.5 ZT4-7 22.1 22.1 22.1 ZT8-11 22.200000000000003 22.200000000000003 22.200000000000003 ZT12-15 10.649999999999999 10.649999999999999 10.649999999999999 ZT16-19 18.049999999999997 18.049999999999997 18.049999999999997 ZT20-23 8.15 8.15 8.15