condition mean min max ZT0-3 14.821552 14.821552 14.821552 ZT4-7 10.175338 10.175338 10.175338 ZT8-11 9.5661375 9.5661375 9.5661375 ZT12-15 14.279311 14.279311 14.279311 ZT16-19 10.971855999999999 10.971855999999999 10.971855999999999 ZT20-23 19.0674755 19.0674755 19.0674755