condition mean min max ZT0-3 11.504515 6.766215000000001 18.890549999999998 ZT4-7 16.65865 16.65865 16.65865 ZT8-11 20.50835 20.50835 20.50835 ZT12-15 27.855 27.7616 27.9484 ZT16-19 22.64095 22.64095 22.64095 ZT20-23 15.3861 15.3861 15.3861