lib/us_geo/population.rb in us_geo-2.0.2 vs lib/us_geo/population.rb in us_geo-2.0.3

@@ -20,7 +20,21 @@
     #
     # @return [Float, nil]
     def population_density_km
       population.to_f / land_area_km if population && land_area.to_f > 0
     end
+
+    # Housing units per square mile.
+    #
+    # @return [Float, nil]
+    def housing_density
+      housing_units.to_f / land_area if housing_units && land_area.to_f > 0
+    end
+
+    # Housing units per square kilometer.
+    #
+    # @return [Float, nil]
+    def housing_density_km
+      housing_units.to_f / land_area_km if housing_units && land_area.to_f > 0
+    end
   end
 end