condition mean min max ZT0-3 18.8 18.8 18.8 ZT4-7 35.8 35.8 35.8 ZT8-11 18.900000000000002 18.900000000000002 18.900000000000002 ZT12-15 33.4 33.4 33.4 ZT16-19 27.0 27.0 27.0 ZT20-23 20.4 20.4 20.4