I'm not sure if this includes album sales, but I'm assuming it doesn't. If so, then the era most definitely sold over 20m records WW (with 23 and Feelin' Myself added). Confirmed numbers had her at ~8m tracks sold in the U.S. and that was without 23, Feelin' Myself, album tracks, or album sales included.
10.1 + 1.5 (23) + 1.1 (album sales) = 12.7m (Since we don't know sales for Fall Down or Feelin' Myself, I'm sure their estimated U.S. sales equal over 300k to makeup the difference). 13m records in the U.S. alone from one era is really impressive.
. Can't wait for the inevitable threads 
. By the by, I just noticed how Miley is tied with Rihanna as the 2nd artist with the most weeks @ 1# on the Billboard Social Top 50 (JB's lead tho 
...). Slay Social Media Queen 
.
