condition mean min max ZT0-3 5.180645 5.180645 5.180645 ZT4-7 1.677495 1.677495 1.677495 ZT8-11 4.556105 4.556105 4.556105 ZT12-15 3.332705 3.332705 3.332705 ZT16-19 5.868 5.868 5.868 ZT20-23 2.548145 2.548145 2.548145