condition mean min max ZT0-3 18.5444 18.5444 18.5444 ZT4-7 10.587615 10.587615 10.587615 ZT8-11 12.00195 12.00195 12.00195 ZT12-15 13.500150000000001 13.500150000000001 13.500150000000001 ZT16-19 24.5054 24.5054 24.5054 ZT20-23 20.1432 20.1432 20.1432