condition mean min max ZT0-3 2.329095 2.1585400000000003 2.49965 ZT4-7 2.359905 2.359905 2.359905 ZT8-11 1.56211 1.56211 1.56211 ZT12-15 0 0 0 ZT16-19 3.22715 3.22715 3.22715 ZT20-23 3.08622 3.08622 3.08622