condition mean min max ZT0-3 31.87835 31.87835 31.87835 ZT4-7 28.4897 28.4897 28.4897 ZT8-11 32.53525 32.53525 32.53525 ZT12-15 36.17615 36.17615 36.17615 ZT16-19 35.931200000000004 35.931200000000004 35.931200000000004 ZT20-23 32.09615 32.09615 32.09615