condition mean min max ZT0-3 28.427866666666667 15.27215 36.281349999999996 ZT4-7 8.351285 8.351285 8.351285 ZT8-11 7.186680000000001 7.186680000000001 7.186680000000001 ZT12-15 11.682425 11.678 11.68685 ZT16-19 15.942250000000001 15.942250000000001 15.942250000000001 ZT20-23 31.33395 31.33395 31.33395