condition mean min max ZT0-3 1.638093 1.008006 2.26818 ZT4-7 1.636635 1.636635 1.636635 ZT8-11 2.14779 2.14779 2.14779 ZT12-15 0 0 0 ZT16-19 2.678715 2.678715 2.678715 ZT20-23 1.771215 1.771215 1.771215