function change_data(){
  url = $F('_form_page');
  if (!$F('month')) return false;
  //var myAjax = new Ajax.Updater('table_currency',url,{parameters: { day:$F('day'), month:$F('month'), year:$F('year') }});
  $('list-error').style.display = $('table_currency').style.display = "none";
  $('progress_currency_table').style.display="";
  var myAjax = new Ajax.Updater('table_currency',url,{parameters:  'day='+$F('day')+'&month='+$F('month')+'&year='+$F('year'), onComplete: response});
}

function response(originalRequest){
  $('table_currency').style.display="";
  $('progress_currency_table').style.display="none";
  if (originalRequest.responseText.strip()=='') $('list-error').style.display="";
  
}