condition mean min max ZT0-3 166.078211 166.078211 166.078211 ZT4-7 189.9941245 189.9941245 189.9941245 ZT8-11 157.07142499999998 157.07142499999998 157.07142499999998 ZT12-15 164.200211 164.200211 164.200211 ZT16-19 134.242693 134.242693 134.242693 ZT20-23 142.0400705 142.0400705 142.0400705