Americans in their late teens and early 20's have very busy thumbs.
95% of 18-24 year olds own a cell phone, and almost all of them text, according to the "Pew Internet and American Life Project."
And they send or receive an average of 109 messages a day.
That's more than double the amount sent or received by people age 25-34.
Researchers surveyed almost 2,300 internet users age 18 and older to get the results.
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