condition mean min max ZT0-3 11.346525 10.8781 11.81495 ZT4-7 8.845424999999999 8.845424999999999 8.845424999999999 ZT8-11 2.816385 2.816385 2.816385 ZT12-15 0 0 0 ZT16-19 1.569985 1.569985 1.569985 ZT20-23 5.02747 5.02747 5.02747