condition mean min max ZT0-3 11.742145505 11.079144750000001 12.40514626 ZT4-7 8.4247731375 8.184257147 8.665289128000001 ZT8-11 9.35794418125 7.5442392575 11.171649105 ZT12-15 8.74135280725 8.528681102 8.9540245125 ZT16-19 9.774451829 8.194798643 11.354105015 ZT20-23 15.118165495 13.452078239999999 16.78425275