condition mean min max ZT0-3 5.13638 3.492175 6.2204 ZT4-7 12.77915 12.77915 12.77915 ZT8-11 36.097449999999995 36.097449999999995 36.097449999999995 ZT12-15 16.56425 12.2363 20.892200000000003 ZT16-19 6.579174999999999 6.579174999999999 6.579174999999999 ZT20-23 6.048954999999999 6.048954999999999 6.048954999999999