condition mean min max ZT0-3 49.908025 44.62765 55.1884 ZT4-7 38.328450000000004 38.328450000000004 38.328450000000004 ZT8-11 36.0938 36.0938 36.0938 ZT12-15 0 0 0 ZT16-19 33.26115 33.26115 33.26115 ZT20-23 50.6015 50.6015 50.6015