condition mean min max ZT0-3 10.696188 10.696188 10.696188 ZT4-7 15.5725185 15.5725185 15.5725185 ZT8-11 28.829964999999998 28.829964999999998 28.829964999999998 ZT12-15 12.8826065 12.8826065 12.8826065 ZT16-19 10.4961255 10.4961255 10.4961255 ZT20-23 11.471105 11.471105 11.471105