Tidy, add spec

app/controllers/admin/prob_data_reports_controller.rb

@@ -12,7 +12,7 @@ def find_prob_data
                          .joins('LEFT JOIN school_groups on schools.school_group_id = school_groups.id')
                          .where(status: 'PROB')
                          .group('school_groups.name', 'schools.name', 'schools.slug', 'meters.meter_type', 'meters.name', :mpan_mprn, 'meters.id')
-                         .order('count(mpan_mprn) DESC')
+                         .order('count(mpan_mprn) DESC, school_groups.name, schools.name')
                          .count
                          .map { |row| row.to_a.flatten }
     end

app/views/admin/prob_data_reports/index.html.erb

@@ -2,14 +2,26 @@
   <%= header_nav_link 'Admin', admin_url %>
 <% end %>
 
-<table class="table table-sorted">
+<p>
+  Lists all of the meters in the system that have one or more "PROB" data readings.
+  These are readings where we have missing data but the analytics has been unable to
+  find a good substitute.
+</p>
+
+<p>
+  The report can be used to identify meters with very poor data quality, as well as
+  examples of where we might improve our substitutions rules.
+</p>
+
+<table id="report" class="table table-sorted">
   <thead>
     <tr>
       <th>School group</th>
       <th>School</th>
-      <th>Meter name/mpan/mprn</th>
+      <th>Meter name</th>
+      <th>MPXN</th>
       <th>Meter type</th>
-      <th>Count of PROB records</th>
+      <th>Count</th>
     </tr>
   </thead>
   <tbody>
@@ -20,8 +32,10 @@
           <%= link_to row[1], school_meters_path(school_id: row[2]) %>
         </td>
         <td>
-          <%= link_to [row[4], row[5]].reject(&:blank?).join(': '),
-                      admin_reports_amr_validated_reading_url(meter_id: row[6]) %>
+          <%= row[4] %>
+        </td>
+        <td>
+          <%= link_to row[5], admin_reports_amr_validated_reading_url(meter_id: row[6]) %>
         </td>
         <td><%= row[3] %></td>
         <td>