condition mean min max ZT0-3 3.9244271177500005 2.9244794360000004 4.924374799500001 ZT4-7 5.20310949425 4.5013751179999995 5.9048438705 ZT8-11 4.5091893835 4.4832545244999995 4.5351242425 ZT12-15 3.8505113302500003 3.389272934 4.3117497265 ZT16-19 5.361236427 4.363241982 6.3592308719999995 ZT20-23 9.195551242 8.9555376215 9.4355648625