condition mean min max ZT0-3 18.773407317500002 17.87617682 19.670637815 ZT4-7 15.750795782500001 15.544175285000001 15.95741628 ZT8-11 18.58705062 15.066893305 22.107207934999998 ZT12-15 15.975515235000001 15.405399880000001 16.545630590000002 ZT16-19 14.3382548575 13.599748175 15.07676154 ZT20-23 16.547569582500003 15.776127835 17.319011330000002