var ayear = null;

var upKeeperTeam = document.onmouseup;
document.onmouseup = doMouseUp;

function doMouseUp(){
	unloadYear();
	upKeeperTeam();
}

function hideYear(){
	unloadYear();
}

function unloadYear(){
	if(ayear){
		if(document.layers){return;}
		if(document.getElementById){
			var lay = document.getElementById("year" + ayear);
			lay.style.visibility = "hidden";
			ayear = null;	
		}
	}
}

function showYear(mid){
	unloadYear();
	clearHide();
	if(document.layers){return;}
	if(document.getElementById){
		var lay = document.getElementById("year" + mid);
		lay.style.visibility = "visible";
		ayear = mid;		
	}
}
// param 1.....9
//layerid = info1...9