function afronden(value)
{    
result=Math.floor(value)+".";    
var cents=100*(value-Math.floor(value))+0.5;    
result += Math.floor(cents/10);    
result += Math.floor(cents%10);    
return result;    
}

function bereken()
{
var unformatted_tax = document.forms[0].totaal.value
var formatted_tax = afronden(unformatted_tax);    
document.forms[0].totaal.value = formatted_tax;
var unformatted_tax = document.forms[0].total.value
var formatted_tax = afronden(unformatted_tax);    
document.forms[0].total.value = formatted_tax; 
var unformatted_tax = document.forms[0].btw.value
var formatted_tax = afronden(unformatted_tax);    
document.forms[0].btw.value = formatted_tax; 

 
}