tax question on sales order

I have an sales order - if I tax each line, the total tax is 19,528.11.when I look at at the order totals in AX - the tax is being reported as 19,528.20 - a .09 cent difference . If you take the order subtotal of 244,101.40 * .08, I get 19,528.11 does anyone know why its off a couple cents?? or what I need to change or check??