condition mean min max ZT0-3 3.2854175000000003 2.6563800000000004 3.9144550000000002 ZT4-7 6.319455 6.319455 6.319455 ZT8-11 4.744465 4.744465 4.744465 ZT12-15 0 0 0 ZT16-19 3.971725 3.971725 3.971725 ZT20-23 5.56429 5.56429 5.56429