update README

Author: Lauri Piispanen

README.md

@@ -37,3 +37,21 @@ This could be due to a number of things.
 2) You live in a city which is not included in the query. Unfortunately the query is free-text and not strictly geographical. Rural areas may be excluded from the list, but you can often remedy this by adding the country name to your location in GitHub.
 
 3) You have mostly private commits. These are included too, but they are not listed on the main country page anymore. Instead you will find a subpage with a list that also has private contributions included. This arrangement is done to favor open source contributions over private contributions.
+
+### Why is my contribution count not the same as on my GitHub profile?
+
+Depending on your settings, your GitHub profile displays either only your public contributions or both your public and private ones. commits.top by default shows only public contributions, but public+private count is accessible on a subpage on each region page. You can use the [GitHub API GraphQL Explorer](https://developer.github.com/v4/explorer/) and run the following query to see what the API returns for your user:
+
+```
+query { 
+  viewer { 
+    login
+    contributionsCollection {
+      restrictedContributionsCount
+      contributionCalendar {
+        totalContributions
+      }
+    }
+  }
+}
+```