condition mean min max ZT0-3 3.97278 2.586755 4.70684 ZT4-7 1.750035 1.750035 1.750035 ZT8-11 1.80922 1.80922 1.80922 ZT12-15 2.505495 2.004195 3.006795 ZT16-19 3.36748 3.36748 3.36748 ZT20-23 4.92442 4.92442 4.92442