U.S. smartwatch sales experienced strong growth in the 12 months ending November 2018 compared to the same timeframe a year prior, according to The NPD Group.

Dollar sales of smartwatches in the U.S. were up 51 percent, totaling nearly $5 billion in sales, while unit sales saw a 61 percent increase.

While Apple is the clear market leader, NPD's data reveals that the top three brands (Apple, Samsung, and Fitbit) made up 88 percent of smartwatch unit sales during the timeframe. However, traditional watch manufacturers, like Fossil, and fitness-focused brands, like Garmin, are working to grow their share of the market, as they continue to expand into the smartwatch category.

“The ability to be truly connected via built-in LTE without the need to have a smartphone nearby proved to be a tipping point for consumers, as they now recognize the value in being able to complete a wide range of tasks on the device including receiving notifications, messaging, accessing smart home controls, and more,” said Weston Henderek, director, industry analyst for NPD Connected Intelligence.

Sixteen percent of U.S. adults now own a smartwatch, which is up from 12 percent in December of 2017, based on NPD’s report. The younger 18-34 age demographic is currently carrying the overall growth in the smartwatch market with 23 percent penetration. However, as newer health focused devices such as the Apple Watch Series 4 continue to take hold in the next year, expect to see a big boost in penetration among older segments. Beyond health and fitness tracking, evolving use cases will help bolster the segment. For example, 15 percent of smartwatch owners now claim to use their devices to control home automation devices.