condition mean min max ZT0-3 12.94914 11.6525 15.419599999999999 ZT4-7 12.51085 12.51085 12.51085 ZT8-11 17.52035 17.52035 17.52035 ZT12-15 21.306424999999997 19.512349999999998 23.1005 ZT16-19 25.0866 25.0866 25.0866 ZT20-23 21.4007 21.4007 21.4007