title: EmberJS Observer Not Firing
body: <p><a href="http://jsbin.com/damowe/3/edit?html,js,output" rel="nofollow">EmberJSBin here</a></p>
  
  <p>I have a component which needs to perform a given operation when any of its values are changed, but the observer I created does not fire:</p>
  
  <pre><code>export default Ember.Component.extend({
      taxes: null,
      NOAYears: 2,
      NOAValues: Ember.computed("NOAYears", function() {
          var NOAs = [],
              lastYear = new Date().getFullYear() - 1;
          for (var year = 0; year &lt; this.get("NOAYears"); year++) {
              NOAs.push({year: lastYear - year, value: 0});
          }
          return NOAs;
      }),
      NOAYearsChanged: function() {
          // does not fire when any of the values change
      }.observes("NOAValues.@each.value")
  });
  </code></pre>
  
  <p>In the component template, I am binding via the <code>{{#each}}</code> iterator:</p>
  
  <pre><code>{{#each NOAValues as |year|}}
      &lt;label for="{{year.year}}-value"&gt;{{year.year}}&lt;/label&gt;
      {{input min="0" step="any" value=year.value required=true placeholder="Yearly Income"}}
  {{/each}}
  </code></pre>
  
  <p>How can I get my observer to fire when any of the <code>value</code> properties in <code>NOAValues</code> is changed?</p>