condition mean min max ZT0-3 21.278100000000002 18.5775 26.48685 ZT4-7 25.283099999999997 25.283099999999997 25.283099999999997 ZT8-11 15.133600000000001 15.133600000000001 15.133600000000001 ZT12-15 16.788175000000003 16.05505 17.5213 ZT16-19 12.09585 12.09585 12.09585 ZT20-23 15.3667 15.3667 15.3667