condition mean min max ZT0-3 12.790043 12.790043 12.790043 ZT4-7 12.995241 12.995241 12.995241 ZT8-11 10.254907 10.254907 10.254907 ZT12-15 11.8715555 11.8715555 11.8715555 ZT16-19 11.9610705 11.9610705 11.9610705 ZT20-23 13.144031 13.144031 13.144031