condition mean min max ZT0-3 3.7348433333333335 3.25441 4.48816 ZT4-7 2.9889150000000004 2.9889150000000004 2.9889150000000004 ZT8-11 4.565645 4.565645 4.565645 ZT12-15 8.687289999999999 7.510305 9.864275 ZT16-19 7.777485 7.777485 7.777485 ZT20-23 7.90052 7.90052 7.90052