condition mean min max ZT0-3 6.27400942525 6.2628093205 6.28520953 ZT4-7 5.534718693 4.3414031785 6.7280342075 ZT8-11 8.664766835750001 7.7277485785 9.601785093 ZT12-15 7.761923428999999 6.5466987045 8.9771481535 ZT16-19 9.314596429 8.2405517285 10.3886411295 ZT20-23 20.475138745000002 14.22613195 26.724145540000002