condition mean min max ZT0-3 1.555222 1.555222 1.555222 ZT4-7 2.940802 2.940802 2.940802 ZT8-11 2.1244870000000002 2.1244870000000002 2.1244870000000002 ZT12-15 1.434756 1.434756 1.434756 ZT16-19 2.9116850000000003 2.9116850000000003 2.9116850000000003 ZT20-23 2.490035333333333 2.490035333333333 2.490035333333333