condition mean min max ZT0-3 39.85 39.85 39.85 ZT4-7 55.6 55.6 55.6 ZT8-11 51.85 51.85 51.85 ZT12-15 33.7 33.7 33.7 ZT16-19 32.699999999999996 32.699999999999996 32.699999999999996 ZT20-23 50.95 50.95 50.95