Add Overall Response Rate Popover

app/presenters/response_rate_presenter.rb

@@ -23,6 +23,10 @@ class ResponseRatePresenter
     percentage > 75 ? 'purple' : 'gold'
   end
 
+  def hover_message
+    "Percentages based on #{ actual_count } out of #{ respondents_count.round } #{ focus }s completing at least 25% of the survey."
+  end
+
   private
 
   def cap_at_100(value)

app/views/overview/_response_rate.html.erb

@@ -1,4 +1,10 @@
-<div class="overall-response-rate-container">
+<div 
+  class="overall-response-rate-container"
+  data-bs-toggle="popover" 
+  data-bs-trigger="hover focus" 
+  data-bs-content="<%= response_rate_presenter.hover_message %>"
+  data-bs-placement="top"
+>
   <div>Response Rates as of <%= response_rate_presenter.date.to_date.strftime("%m/%d/%y") %> </div>
   <div style="display: flex; justify-content:space-between; width: 100px;">
   <div><%= response_rate_presenter.focus.capitalize %> </div>