condition mean min max ZT0-3 7.87111111 7.87111111 7.87111111 ZT4-7 6.497222222 6.497222222 6.497222222 ZT8-11 6.447222222 6.447222222 6.447222222 ZT12-15 5.26 5.26 5.26 ZT16-19 4.208888889 4.208888889 4.208888889 ZT20-23 4.846666667 4.846666667 4.846666667