// JavaScript Document

function CalculateRepayment() {
	var formCalc;
	if( formCalc = document.getElementById( 'formCalc' ) )
	{
		var loanamount= formCalc.muamount.value;
		var interest= formCalc.muinterest.value;
		var term =getmenuvalue(formCalc.muterm);
		var I= interest/12;
		var X=1/(1+I/100);
		var N= term *12;
		formCalc.txtrepay.value = formatnumber(loanamount*(X-1)/(Math.pow(X,N+1)-X));
		formCalc.txtinterest.value=formatnumber((loanamount-loanamount*Math.pow(X,N))*(X-1)/(Math.pow(X,N+1)-X));
	}
}	
function getmenuvalue(obj){
 return (obj.options[obj.selectedIndex].value);
}

function formatnumber(n) {
	return Math.round(n*100)/100;
}