condition mean min max ZT0-3 12.84045 12.84045 12.84045 ZT4-7 11.800295 11.800295 11.800295 ZT8-11 10.300645 10.300645 10.300645 ZT12-15 11.64505 11.64505 11.64505 ZT16-19 12.24925 12.24925 12.24925 ZT20-23 12.67875 12.67875 12.67875