Have a layer resize script, but need it to work when layer is great than 550px

Hi,

I've luckily found a script that does a layer resize just what was needed. Only thing is, I want the script to only deploy if that current layer is greater than 550px - existing code for the script is below:

(function (){
    var startRulerUnits = app.preferences.rulerUnits;  
    app.preferences.rulerUnits = Units.PIXELS;
    var bounds = activeDocument.activeLayer.bounds;  
    var width = bounds[2].value - bounds[0].value;
    var newSize = (100 / width) * 550;  
    activeDocument.activeLayer.resize(newSize, newSize, AnchorPosition.BOTTOMLEFT);
    app.preferences.rulerUnits = startRulerUnits;  
})();

If anyone can explain how I can use an If function, would be much appreciated!

Many thanks in anticipation.