condition mean min max ZT0-3 12.2085775 8.89769 15.519465 ZT4-7 5.37241 5.37241 5.37241 ZT8-11 4.75587 4.75587 4.75587 ZT12-15 0 0 0 ZT16-19 6.463555 6.463555 6.463555 ZT20-23 13.5731 13.5731 13.5731