condition mean min max ZT0-3 38.666163 38.666163 38.666163 ZT4-7 47.370322 47.370322 47.370322 ZT8-11 42.63696 42.63696 42.63696 ZT12-15 41.997137 41.997137 41.997137 ZT16-19 42.10815 42.10815 42.10815 ZT20-23 36.6020835 36.6020835 36.6020835