Merge pull request #238 from GEMDAT-repos/fix_occupancy

Fix number of sites by type

src/gemdat/sites.py

@@ -382,7 +382,9 @@ def _calculate_site_occupancy(
         label = labels[k]
         counts[label].append(v)
 
-    div = len(labels) * n_steps
-    site_occupancies = {k: sum(v) / div for k, v in counts.items()}
+    site_occupancies = {
+        k: sum(v) / (n_steps * labels.count(k))
+        for k, v in counts.items()
+    }
 
     return site_occupancies