condition mean min max ZT0-3 7.02183 7.02183 7.02183 ZT4-7 5.9922249999999995 5.9922249999999995 5.9922249999999995 ZT8-11 4.371785 4.371785 4.371785 ZT12-15 4.938124999999999 4.938124999999999 4.938124999999999 ZT16-19 5.992675 5.992675 5.992675 ZT20-23 5.491975 5.491975 5.491975