Add new stat

app/controllers/api/v1/stats_controller.rb

@@ -3,6 +3,7 @@ module Api::V1
     def index
       @park_count = Park.count
       @alert_count = Alert.count
+      @state_with_most_parks = ParksByState.group(:state).count.max
       @park_with_most_alerts = Alert.group(:park_code).count.max
     end
   end

app/views/api/v1/stats/index.json.jbuilder

@@ -1,6 +1,10 @@
 json.park_count @park_count
 json.alert_count @alert_count
-json.most_alerts do
+json.state_with_most_parks do
+  json.state @state_with_most_parks[0]
+  json.park_count @state_with_most_parks[1]
+end
+json.park_with_most_alerts do
   json.park_code @park_with_most_alerts[0]
   json.alert_count @park_with_most_alerts[1]
 end