function showSubListing(showYear,yearImg) {
	var isShown = document.getElementById(showYear);

	if (isShown.style.display == "block") {
		isShown.style.display = "none";
		document.getElementById(yearImg).src="images/plus.gif";
	}
	else {
		isShown.style.display = "block";
		document.getElementById(yearImg).src="images/minus.gif";
	}


}