condition mean min max ZT0-3 1.47000007875 0.7828384209999999 2.1571617365 ZT4-7 3.9385927405000003 3.2084055420000004 4.668779939 ZT8-11 7.9445932159999995 6.6191886065 9.269997825499999 ZT12-15 10.027627608500001 9.426503734 10.628751483 ZT16-19 7.229535311999999 7.1353904109999995 7.323680212999999 ZT20-23 6.26735834675 5.7520101115 6.782706582