condition mean min max ZT0-3 29.299999999999997 29.299999999999997 29.299999999999997 ZT4-7 28.1 28.1 28.1 ZT8-11 25.900000000000002 25.900000000000002 25.900000000000002 ZT12-15 23.35 23.35 23.35 ZT16-19 5.0 5.0 5.0 ZT20-23 13.6 13.6 13.6