condition mean min max ZT0-3 51.400000000000006 51.400000000000006 51.400000000000006 ZT4-7 44.9 44.9 44.9 ZT8-11 31.3 31.3 31.3 ZT12-15 47.95 47.95 47.95 ZT16-19 50.349999999999994 50.349999999999994 50.349999999999994 ZT20-23 60.8 60.8 60.8