condition mean min max ZT0-3 52.242297 52.242297 52.242297 ZT4-7 50.5690255 50.5690255 50.5690255 ZT8-11 49.700559 49.700559 49.700559 ZT12-15 31.156838 31.156838 31.156838 ZT16-19 21.701784500000002 21.701784500000002 21.701784500000002 ZT20-23 20.396654499999997 20.396654499999997 20.396654499999997