condition mean min max ZT0-3 12.48002 12.48002 12.48002 ZT4-7 12.667131999999999 12.667131999999999 12.667131999999999 ZT8-11 12.5489925 12.5489925 12.5489925 ZT12-15 13.323296500000001 13.323296500000001 13.323296500000001 ZT16-19 12.416459 12.416459 12.416459 ZT20-23 13.5414395 13.5414395 13.5414395