condition mean min max ZT0-3 2.15494 1.9524 2.35748 ZT4-7 3.072575 3.072575 3.072575 ZT8-11 2.90935 2.90935 2.90935 ZT12-15 0 0 0 ZT16-19 3.181755 3.181755 3.181755 ZT20-23 3.7532900000000002 3.7532900000000002 3.7532900000000002