It depends on the number of points you are using, so your length of stay, season and room type. We can't help unless we have this information. I'm not sure if this is allowed, moderators please remove if this shouldn't be here. But here is the chart, found on the DVC website regarding the tax..
The 2015 TAT rate will not be available until the new Annual Dues amount for 2015 comes out with the notices for the annual meeting, late November or early December.