condition mean min max ZT0-3 275.847441 275.847441 275.847441 ZT4-7 481.568063 481.568063 481.568063 ZT8-11 611.322954 611.322954 611.322954 ZT12-15 704.436537 704.436537 704.436537 ZT16-19 484.3576795 484.3576795 484.3576795 ZT20-23 443.9322505 443.9322505 443.9322505