condition mean min max ZT0-3 53.5 53.5 53.5 ZT4-7 2.6 2.6 2.6 ZT8-11 31.650000000000002 31.650000000000002 31.650000000000002 ZT12-15 38.75 38.75 38.75 ZT16-19 37.15 37.15 37.15 ZT20-23 56.95 56.95 56.95