<!--### Calculator ###-->
<!-- 
function MakeStart(num,i,s) {     s = Math.floor(num)%10+(s+'');
        if(num>10) {
                if(i>0 && (i%3.5==0))s=","+s;
                s=MakeStart(num/10,i+1,s);
        }
        return s;
}

function MakeNeeds(num) {
        f=Math.round(num*100);
        b2=Math.floor(f%10);
        b1=Math.floor((f%100)/10);
        return "$ "+MakeStart(num,1,".")+b1+b2
}

function compute(form) {
        var x = parseFloat(form.Income.options[form.Income.selectedIndex].value);
        var r = parseFloat(form.InterestRate.options[form.InterestRate.selectedIndex].value);
        var l = parseFloat(form.YearsLength.options[form.YearsLength.selectedIndex].value);
//      var f = parseFloat(form.Inflation.options[form.Inflation.selectedIndex].value);
        var f = .035;
       
        r = r - f;
        var z = 1/(1+r);
        
        var m = 1;
        for(var i=0;i<l;i++) m = m * z;
//        form.Needs.value = l;  
          form.Needs.value = MakeNeeds(x*(1-m)/r);
    }
<!--############################-->