code: function (keyName, decrement) {
        if (_emberMetalIs_none.default(decrement)) {
          decrement = 1;
        }
        _emberMetalDebug.assert('Must pass a numeric value to decrementProperty', !isNaN(parseFloat(decrement)) && isFinite(decrement));
        return _emberMetalProperty_set.set(this, keyName, (_emberMetalProperty_get.get(this, keyName) || 0) - decrement);
      }
docs: Set the value of a property to the current value minus some amount.
  ```javascript
  player.decrementProperty('lives');
  orc.decrementProperty('health', 5);
  ```
  @method decrementProperty
  @param {String} keyName The name of the property to decrement
  @param {Number} decrement The amount to decrement by. Defaults to 1
  @return {Number} The new property value
  @public