condition mean min max ZT0-3 1.8843779999999999 1.8843779999999999 1.8843779999999999 ZT4-7 1.7781420000000001 1.7781420000000001 1.7781420000000001 ZT8-11 2.02617 2.02617 2.02617 ZT12-15 1.667835 1.667835 1.667835 ZT16-19 2.85973 2.85973 2.85973 ZT20-23 1.0098426666666667 1.0098426666666667 1.0098426666666667