condition mean min max ZT0-3 53.900000000000006 53.900000000000006 53.900000000000006 ZT4-7 76.2 76.2 76.2 ZT8-11 71.55 71.55 71.55 ZT12-15 42.0 42.0 42.0 ZT16-19 23.9 23.9 23.9 ZT20-23 58.05 58.05 58.05