function startEndDate() 
{
    
    
  from=document.f3.date_from.value
  to=document.f3.date_to.value
   
  var interessi;
  var sanzioni;
  var giorni;
  
  var fromArray = from.split('/');
  
  
  fromdate = new Date( fromArray[2], fromArray[1]-1, fromArray[0]);
   
  var toArray = to.split('/');
  todate = new Date( toArray[2], toArray[1]-1, toArray[0]);
  
  if (isNaN((todate-fromdate)/86400000) == true)
  {
      document.f3.daynums.value=0;
  }
  else
  {
    if(((todate-fromdate)/86400000) < 0)
    {
      document.f3.daynums.value=0;
    }
    else
    {
     document.f3.daynums.value=(todate-fromdate)/86400000;
    }
  }
  giorni=document.f3.daynums.value;
  document.f3.daynums.value=Math.round(giorni);
  interessi=(((document.f3.tributo.value)*0.015)/365)*document.f3.daynums.value;
  document.f3.interessi.value=interessi.toFixed(2);
  
  
   if((document.f3.daynums.value) <30)
   {
     document.f3.sanzioni.value=document.f3.tributo.value*0.03;
   }
   if((document.f3.daynums.value>30) && (document.f3.daynums.value<365))
   {
     document.f3.sanzioni.value=document.f3.tributo.value*0.0375;
   }
       
   if(document.f3.daynums.value>365) 
   {
     document.f3.sanzioni.value=document.f3.tributo.value*0.3;
   }
  
   
   if (document.f3.check.checked==true)
   {
     document.f3.sanzioni.value=document.f3.tributo.value*0.3;
   }

   
  
}