condition mean min max ZT0-3 28.3 28.3 28.3 ZT4-7 18.1 18.1 18.1 ZT8-11 25.400000000000002 25.400000000000002 25.400000000000002 ZT12-15 20.95 20.95 20.95 ZT16-19 17.95 17.95 17.95 ZT20-23 23.4 23.4 23.4