condition mean min max ZT0-3 3.3873321494999997 2.652952426 4.121711873 ZT4-7 4.8659828767499995 4.77541512 4.9565506335 ZT8-11 2.2748670622500002 1.414603659 3.1351304655 ZT12-15 1.01621411175 0.864094878 1.1683333455 ZT16-19 2.8164336372500003 1.8536983710000001 3.7791689035 ZT20-23 10.1627217265 9.4696127755 10.8558306775