condition mean min max ZT0-3 4.396850000000001 3.15566 5.63804 ZT4-7 3.291585 3.291585 3.291585 ZT8-11 13.6343 13.6343 13.6343 ZT12-15 0 0 0 ZT16-19 13.6341 13.6341 13.6341 ZT20-23 9.40327 9.40327 9.40327