condition mean min max ZT0-3 3.40198 3.40198 3.40198 ZT4-7 2.098355 2.098355 2.098355 ZT8-11 2.6005000000000003 2.6005000000000003 2.6005000000000003 ZT12-15 3.42296 3.42296 3.42296 ZT16-19 4.69545 4.69545 4.69545 ZT20-23 3.8090349999999997 3.8090349999999997 3.8090349999999997