condition mean min max ZT0-3 23.900000000000002 23.900000000000002 23.900000000000002 ZT4-7 15.0 15.0 15.0 ZT8-11 22.0 22.0 22.0 ZT12-15 37.1 37.1 37.1 ZT16-19 31.25 31.25 31.25 ZT20-23 20.55 20.55 20.55