condition mean min max ZT0-3 36.080525 30.226100000000002 41.93495 ZT4-7 12.150549999999999 12.150549999999999 12.150549999999999 ZT8-11 9.64514 9.64514 9.64514 ZT12-15 0 0 0 ZT16-19 21.198 21.198 21.198 ZT20-23 23.229300000000002 23.229300000000002 23.229300000000002