resize method with Javascript in Illustrator CS4

var objectBounds = docRef.visibleBounds;

var W = objectBounds[2] - objectBounds[0]; //figures the width

var H = objectBounds[1] - objectBounds[3]; //figures the height

// W & H are reporting the size in points ... convert to picas

var picaW = W / 12;

var picaH = H / 12;

// do the math for the correct column width: settings / width = percentage in decimal; multiply by 100 to get the decimal place in the right spot.

var endWidth

var percentageX = Math.round((endWidth / picaW) * 100);

var percentageY = percentageX;

for (var a=0; a<docRef.layers.length; a++){

     var layerRef = docRef.layers;

     layerRef.hasSelectedArtwork=true;   // select all

     // now to resize based on the percentage

     layerRef.pageItem.resize(percentageX, percentageY);

}

The width and height are coming out fine. But in this last line, that resize is just not working. When I run it I get an error that says: undefined is not an object.

The syntax must be wrong ... any ideas?

Thanks in advance!