// JavaScript Document

function filterNum(str) {
	re = /^\$|,/g;
	// remove "$" and ","
	return str.replace(re, "");
}

function getrate() {
	V = filterNum(document.getElementById("v").value);
	F = filterNum(document.getElementById("f").value);
	var num = new Number(F / V * 100);
	document.getElementById("r").value = "%" + num.toFixed(3);
}