Perhaps you can calculate your course progress by dividing crown level by total number of crowns ( x 100) to find the percentage : https://www.duolingo.com/comment/26868710

Each skill on your tree has a maximum of 5 levels, the general crown level on the upper right corner is simply the sum of the crown levels of all skills. The maximum crown level is therefore 5 times the amount of skills on the tree.

Thanks for responding and your feedback was helpful.