function validateForm() {
  var returnValue = new Boolean();
  var dayUsage = document.getElementById("dayUsage");
  var changes = document.getElementById("changes");
  var oldChange = document.getElementById("oldChange");
  if (dayUsage.value*10>oldChange.value*changes.value/360) {
    returnValue=true;
  } else {
    alert("According to your entries, the time you spend changing tools exceeds the daily machine usage.\nPlease adjust the Machine Daily Usage, Tool Channge Time, and Number of Tool Changes entries to accurately model you kneemill usage.");
    dayUsage.focus();
    dayUsage.select();
    returnValue=false;
  }
  return returnValue;
}