condition mean min max ZT0-3 2.1733975 2.013715 2.33308 ZT4-7 3.1729950000000002 3.1729950000000002 3.1729950000000002 ZT8-11 4.585165 4.585165 4.585165 ZT12-15 0 0 0 ZT16-19 4.814045 4.814045 4.814045 ZT20-23 4.49389 4.49389 4.49389