condition mean min max ZT0-3 50.8 50.8 50.8 ZT4-7 52.4 52.4 52.4 ZT8-11 36.400000000000006 36.400000000000006 36.400000000000006 ZT12-15 46.6 46.6 46.6 ZT16-19 51.900000000000006 51.900000000000006 51.900000000000006 ZT20-23 55.3 55.3 55.3