condition mean min max ZT0-3 5.1151075 5.087755 5.14246 ZT4-7 5.3606300000000005 5.3606300000000005 5.3606300000000005 ZT8-11 6.173945 6.173945 6.173945 ZT12-15 0 0 0 ZT16-19 8.57766 8.57766 8.57766 ZT20-23 6.884125 6.884125 6.884125