condition mean min max ZT0-3 942.499493 942.499493 942.499493 ZT4-7 1109.9154835 1109.9154835 1109.9154835 ZT8-11 949.3213384999999 949.3213384999999 949.3213384999999 ZT12-15 837.2291095 837.2291095 837.2291095 ZT16-19 603.341629 603.341629 603.341629 ZT20-23 498.120722 498.120722 498.120722