In May, 2003 the entire U.S. sent 300MM texts. In 2011 people in the U.S. send nearly 2B a day.

Added: 12/19/2011 from Mobile Marketing Association Published: 12/19/2011

Text messaging users in the US send or receive an average of 35 messages per day more...

U.S. consumers send 2.304T text messages per year, up from 2.052T in 2010 more...

The volume of texting among teens has risen from 50 texts a day in 2009 to 60 texts for the median teen text user in 2012 more...

75% of U.S. mobile subscribers send text messages, 49% download apps and 49% use Internet browsers more...

47% of all text-using adults have texted while driving more...