U.S. wireless users set another record for mobile data consumption last year, according to a new industry report.

The results of CTIA's Annual Wireless Industry Survey indicated that Americans used 15.7 trillion megabytes of data in 2017, a 14.3 percent increase compared to 2016 and about four times the amount of data used in 2014.

In addition, the 323,448 cell sites in operation at the end of the year also set a U.S. record. Cell sites increased 5 percent compared to 2016 and were up more than 50 percent over the past decade — a pattern that CTIA officials said represented the beginning of investment in the hundreds of thousands of small cellular sites needed to build 5G networks.

Another sign of the shift to 5G and the Internet of Things, the group added, was a nearly 20 percent year-over-year jump in data-only devices, such as wearables, IoT devices and connected cars.

"This year’s report shows that wireless is on the cusp of a transformation to tomorrow's 5G networks and the Internet of Things, underscoring the need for continued efforts to modernize infrastructure rules and create a spectrum pipeline that ensures continued U.S. wireless leadership in the global race to 5G," CTIA President and CEO Meredith Attwell Baker said in a statement.

The number of overall wireless connections edged up to more than 400 million in the latest survey, with smartphones climbing from nearly 262 million in 2016 to more than 273 million last year.

The group also said the wireless industry spent $25.6 billion in capital expenditures in 2017.