This website reviews results from 1999 through 2019 of the marathon-length American Birkebeiner cross country ski race. The dataset has recently been updated through 2019 and focuses initially on how age affects performance. The updated summary is under Graphs and Tables 1999-2019. Updates will continue over the next several months.

For more, see Overview or go directly to Graphs & Tables 1999-2019 (and use the "i" button for more information for each graph.)

The previous 1999-2016 summary is available here.