condition mean min max ZT0-3 3.8959200000000003 3.60998 4.18186 ZT4-7 2.5376950000000003 2.5376950000000003 2.5376950000000003 ZT8-11 2.989585 2.989585 2.989585 ZT12-15 0 0 0 ZT16-19 6.67708 6.67708 6.67708 ZT20-23 3.7243150000000003 3.7243150000000003 3.7243150000000003