condition mean min max ZT0-3 7.805695 6.722775 8.888615 ZT4-7 5.049585 5.049585 5.049585 ZT8-11 5.186205 5.186205 5.186205 ZT12-15 0 0 0 ZT16-19 7.327725 7.327725 7.327725 ZT20-23 6.629020000000001 6.629020000000001 6.629020000000001