As long as you're on the subject of "Forever" Stamps, what do you think of this statistic carried on one of the USPS's web sites?

Using that calculation:
20.8 billion stamps sold and 84% were "Forever" stamps = 17.48 billion "Forever" stamps were sold in 2012.
When one looks at the fact that the USPS has issued slightly less than 11.5 billion stamps in all of 2012 (according to Postal Bulletin specs for each new issue), does this suggest that nearly 6 billion stamps were sold in 2012 from previous years? Or does the USPS reprint stamps far above and beyond the quoted quantities as published in the Postal Bulletin?
Remember, we are only talking about "Forever" stamps (not denominated ones) so high value stamps, and those used for Express Mail and Priority Mail are not included in this count. Further, we are talking about stamps
sold, not just those actually used for postage.