function stampduty(dutyform) 
{
	var amount = dutyform.amount.value;

	if (amount == "") 
	{
		amount = 0;
		window.alert("You have not entered a value!");
	}


	if ((amount % 100) != 0 ) 
	{
		var mod = eval(100-(amount % 100));
		amount = -(-amount - mod);
	}


	if (amount <= 25000) {
		var duty = amount * ( 1.4/100 );
	}

	else if ((amount > 25000) && (amount <= 130000)) {
		var duty = ( amount - 25000 ) * ( 2.4/100 ) + 350;
	}

	else if ((amount > 130000) && (amount <= 440000)) {
		var duty = ( amount - 130000 ) * ( 5/100 ) + 2870;
	}

	else if ((amount > 440000) && (amount <= 550000)) {
		var duty = ( amount - 440000 ) * ( 6/100 ) + 18370;
	}

	else if ((amount > 550000) && (amount <= 960000)) {
		var duty = ( amount - 550000 ) * ( 6/100 ) + 28070;
	}

	else {
		var duty = amount * ( 5.5/100 );
	}

	duty = Math.round(duty);
	dutyform.duty.value = duty;
	return false;
}