condition mean min max ZT0-3 15.27222222 15.27222222 15.27222222 ZT4-7 8.872777778 8.872777778 8.872777778 ZT8-11 12.969999999999999 12.969999999999999 12.969999999999999 ZT12-15 7.925555555666667 7.925555555666667 7.925555555666667 ZT16-19 12.097777779000001 12.097777779000001 12.097777779000001 ZT20-23 10.607777777666668 10.607777777666668 10.607777777666668