condition mean min max ZT0-3 2.1063025 1.54024 2.672365 ZT4-7 1.630915 1.630915 1.630915 ZT8-11 4.235825 4.235825 4.235825 ZT12-15 0 0 0 ZT16-19 9.639815 9.639815 9.639815 ZT20-23 0.665392 0.665392 0.665392