condition mean min max ZT0-3 5.24847191 2.329421642 8.167522178 ZT4-7 5.1690507985 4.6932357595 5.644865837499999 ZT8-11 6.26336296575 6.135765953 6.3909599785 ZT12-15 9.3955653955 6.7046329175 12.0864978735 ZT16-19 21.4362987075 18.609185150000002 24.263412265 ZT20-23 20.103694155 19.200992069999998 21.00639624