condition mean min max ZT0-3 7.2476525 6.650335 7.84497 ZT4-7 4.60855 4.60855 4.60855 ZT8-11 5.182695 5.182695 5.182695 ZT12-15 0 0 0 ZT16-19 12.263145 12.263145 12.263145 ZT20-23 10.93 10.93 10.93