condition mean min max ZT0-3 6.9939350000000005 6.66486 7.32301 ZT4-7 5.102395 5.102395 5.102395 ZT8-11 5.9596800000000005 5.9596800000000005 5.9596800000000005 ZT12-15 0 0 0 ZT16-19 5.9086549999999995 5.9086549999999995 5.9086549999999995 ZT20-23 6.333475 6.333475 6.333475