condition mean min max ZT0-3 14.09218 8.72799 17.38005 ZT4-7 9.632535 9.632535 9.632535 ZT8-11 7.617555 7.617555 7.617555 ZT12-15 13.70897 9.60794 17.810000000000002 ZT16-19 15.7667 15.7667 15.7667 ZT20-23 14.9293 14.9293 14.9293