Best design for summarizing Rally dependency data

Question

Rally API documentation for reference

I am using looking to use the Rally SDK to build an interactive, User Story dependency report.

I am struggling to figure out the best way to structure the data in order to render a table (a.k.a a grid) showing the count of dependencies (predecessors and successors) that projects have with other projects that is then filterable by time (release and/or iteration).

With the SDK, I am able to get to the data

Ext.Array.each(stories, function(story) {
   var project = story.get('Project');
   var release = story.get('Release');
   var iteration = story.get('Iteration');
                        
   var dependencyCount = 0;

   console.log('Getting dependency information');

   story.getCollection('Predecessors').load({
       fetch: ['FormattedID', 'Name', 'Release', 'Iteration'],
       callback: function(predecessors, operation, success) {
           Ext.Array.each(predecessors, function(predecessor) {
               var dependentOnProjectId = predecessor.get('FormattedID');
               var dependentOnProjectName = predecessor.get('Name');
               var dependentOnRelease = predecessor.get('Release');
               var dependentOnIteration = predecessor.get('Iteration');

               //not sure what to do here to set the data up
           });
       }
   });
});

I am trying to view the data in a grid like so...

The grid will then be filterable by release and/or iteration.

This approach could be all wrong as well.

Thank you in advance for any help.