function compute(formfield) {
	browserName = navigator.appName;
	browserVer = parseInt(navigator.appVersion);
	if (browserName == "Microsoft Internet Explorer" && browserVer >=4) version = "yes"
	else version ="no";
	x = StripChars(formfield.Income.value);
	if (x == "") {
		window.alert("Please enter your income!");
	}
	else {
		x = parseFloat(x);
		if (x <=6000) {
			pretax = 0;
			posttax = 0;
		}
		if (x > 6000 && x <= 20000) {
			pretax = (x - 6000) * 0.17;
			posttax = pretax;
			pretaxrate = 17
			posttaxrate = 17
		}
		if (x > 20000 && x <= 21600) {
			pretax = 2380 + ((x - 20000) * 0.30);
			posttax = (x - 6000) * 0.17;
			pretaxrate = 30
			posttaxrate = 17
		}
		if (x > 21600 && x <= 50000) {
			pretax = 2380 + ((x - 20000) * 0.30);
			posttax = 2652 + ((x - 21600) * 0.30);
			pretaxrate = 30
			posttaxrate = 30
		}
		if (x > 50000 && x <= 52000) {
			pretax = 11380 + ((x - 50000) * 0.42);
			posttax = 2652 + ((x - 21600) * 0.30);
			pretaxrate = 42
			posttaxrate = 30
		}
		if (x > 52000 && x <= 60000) {
			pretax = 11380 + ((x - 50000) * 0.42);
			posttax = 11772 + ((x - 52000) * 0.42);
			pretaxrate = 42
			posttaxrate = 42
		}
		if (x > 60000 && x <= 62500) {
			pretax = 15580 + ((x - 60000) * 0.47);
			posttax = 11772 + ((x - 52000) * 0.42);
			pretaxrate = 47
			posttaxrate = 42
		}
		if (x > 62500) {
			pretax = 15580 + ((x - 60000) * 0.47);
			posttax = 16182 + ((x - 62000) * 0.47);
			pretaxrate = 47
			posttaxrate = 47
		}
		//prepa = (x * 0.985 - pretax);
		//postpa = (x * 0.985 - posttax);
		prepa = (x - pretax);
		postpa = (x - posttax);
		premth = prepa / 12
		postmth = postpa / 12
		prewk = prepa / 52;
		postwk = postpa / 52;
	
		if (version == "yes") {
			if (postwk - prewk >=0) {
//				document.all.diffwk.style.color = "#3366CC";
				formfield.diffwk.value = rounding(postwk - prewk) + " less tax";
				formfield.diffwk04.value = rounding(postwk - prewk) + " less tax";
			}
			else {
//				document.all.diffwk.style.color = "#FF0000";
				formfield.diffwk.value = rounding(postwk - prewk) + " more tax";
				formfield.diffwk04.value = rounding(postwk - prewk) + " more tax";
			}
		}
//		formfield.diffwk.value = "$" + rounding(postwk - prewk);
		formfield.PreTax.value = rounding(pretax);
		formfield.PostTax.value = rounding(posttax);
		formfield.PostTax04.value = rounding(posttax);
		formfield.PreTaxAnnum.value = rounding(prepa);
		formfield.PostTaxAnnum.value = rounding(postpa);
		formfield.PostTaxAnnum04.value = rounding(postpa);
		formfield.PreTaxMonth.value = rounding(premth);
		formfield.PostTaxMonth.value = rounding(postmth);
		formfield.PostTaxMonth04.value = rounding(postmth);
		formfield.PreTaxWeek.value = rounding(prewk);
		formfield.PostTaxWeek.value = rounding(postwk);
		formfield.PostTaxWeek04.value = rounding(postwk);
		formfield.PreTaxRate.value = pretaxrate;
		formfield.PostTaxRate.value = posttaxrate;
		formfield.PostTaxRate04.value = posttaxrate;
// Originally had the $ sign in the display		formfield.PostTaxWeek.value = "$" +rounding(postwk);
 	}
}

function rounding(n) {
	pennies = n * 100 ;
	pennies = Math.round(pennies) ;
	strPennies = "" + pennies ;
	len = strPennies.length ;
	return strPennies.substring(0, len - 2) + "." + strPennies.substring((len - 2), len);
}
function StripChars(strIn) {
	var newstr = "";
	var Chars = "0123456789.";
    for (var i = 0; i < strIn.length; i++) {
       if (Chars.indexOf(strIn.charAt(i)) == -1) {}
	   else {
	   	newstr = newstr + strIn.charAt(i);
	   }
    }
	return newstr;
}