Kindle-Fire
Kindle-Fire Reuters

The number of U.S. consumers who own tablets, e-readers, or both nearly doubled following the holiday season, according to a report released Monday.

Nineteen percent of Americans owned a tablet by early January, the Pew Research Center estimated, up from 10 percent in mid-December. The same percentage of people owned a e-reader by early January, up from 10 percent in mid-December as well.

In all, 29 percent of Americans owned at least one of the devices by January, up from 18 percent in mid-December.

Most likely to own one or both of the devices were those between the ages of 30 and 49, college graduates and those with a household income of $75,000 or more. Least likely owners were those aged 65 and over, those without a high school degree and those with a annual household income of less than $30,000.

Surveyors pointed to the decrease in price for both devices. In response to Apple's iPad2 tablets, which cost $499, Amazon introduced the Kindle Fire, which lists for $199. Barnes & Noble also began sales of the Nook Color, which costs the same as a Kindle Fire. Furthermore, the price of e-readers dropped significantly, with some Kindle and Nook e-readers costing under $100.

Amazon announced it was selling more than a million Kindles each week last month, with much of the growth coming from the Kindle Fire tablet. International Business Times reported in November that Amazon's Fire would cost the Seattle-based retailer $50 for each device sold. However, over time the device could actually yield $136 per device in content sales, according to estimates from RBC Capital.

The increase in tablets and e-readers has had a significant effect on traditional book sales. Barnes & Noble has struggled in recent quarters with declining book sales. Some of those losses have been offset by the Nook, and the company announced it is considering spinning off its Nook sales into a separate company unit. Rival bookseller Borders collapsed last year.

Amazon shares were off $5.23 to $185.70 midday Monday, while Barnes & Noble shares fell 30 cents to $11.73.