public double calcTotalTax(ArrayList<Product> prodList){
		double totalTax = 0.0;

		//Calculate the tax value which is the difference between the taxed cost and original cost.
		for(Product p : prodList) {
			totalTax += (p.getTaxedCost() - p.getPrice());
		}
		return RoundTax.truncate(totalTax);
	}