start_ix = 0;
reasons = false;

window.onload = function init(){
	reasons = $$("ul#top_reasons li");
	
	reasons.each(
		function(li){
			li.hide();
		}
	);

	window.setInterval(update,1250);
}

function update(){
	prev_ix = start_ix - 1;
	
	if(prev_ix < 0){
		prev_ix = prev_ix + reasons.length;
	}

	reasons[prev_ix].hide();

	for(var ix=0; ix<5; ix++){
		current_ix = start_ix + ix;
		if(current_ix >= reasons.length){
			current_ix = current_ix - reasons.length;
		}
		reasons[current_ix].show();
	}	

	if(start_ix++ >= reasons.length){
		start_ix = start_ix - reasons.length;
	}	
}