condition mean min max ZT0-3 6.95695 6.95695 6.95695 ZT4-7 6.755255 6.755255 6.755255 ZT8-11 7.678850000000001 7.678850000000001 7.678850000000001 ZT12-15 6.514155000000001 6.514155000000001 6.514155000000001 ZT16-19 8.66477 8.66477 8.66477 ZT20-23 7.097405 7.097405 7.097405