code: function(geometry) {
          var units = this.displaySystemUnits[this.displaySystem];
          var unit, area;
          for(var i=0, len=units.length; i<len; ++i) {
              unit = units[i];
              area = this.getArea(geometry, unit);
              if(area > 1) {
                  break;
              }
          }
          return [area, unit];
      }
docs: Method: getBestArea
  Based on the <displaySystem> returns the area of a geometry.
  
  Parameters:
  geometry - {<OpenLayers.Geometry>}
  
  Returns:
  {Array([Float, String])}  Returns a two item array containing the
  area and the units abbreviation.