condition mean min max ZT0-3 2.05896 2.05896 2.05896 ZT4-7 1.44863 1.44863 1.44863 ZT8-11 1.4696150000000001 1.4696150000000001 1.4696150000000001 ZT12-15 1.8268550000000001 1.8268550000000001 1.8268550000000001 ZT16-19 1.542975 1.542975 1.542975 ZT20-23 1.799525 1.799525 1.799525