condition mean min max ZT0-3 8.229915 8.229915 8.229915 ZT4-7 8.315355 8.315355 8.315355 ZT8-11 12.40755 12.40755 12.40755 ZT12-15 10.8048 10.8048 10.8048 ZT16-19 11.500250000000001 11.500250000000001 11.500250000000001 ZT20-23 5.4161649999999995 5.4161649999999995 5.4161649999999995