condition mean min max ZT0-3 9.972663 9.972663 9.972663 ZT4-7 11.2673125 11.2673125 11.2673125 ZT8-11 10.060989500000002 10.060989500000002 10.060989500000002 ZT12-15 9.1571635 9.1571635 9.1571635 ZT16-19 10.278468 10.278468 10.278468 ZT20-23 10.479923 10.479923 10.479923