Viewing hours of over-the-top, internet-delivered video grew by 114% in the first quarter of 2018 from a year ago, according to a new report from Conviva.

Total viewing of movies, episodic TV shows, live linear TV and live sports on mobile, connected TV and desktop screens reached nearly five billion hours, .

Conviva uses an all-screen census measurement approach that captures data about streams played, viewing hours, devices and regions. It also gauges video start times, buffering time and bit rates.

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“Because the complexity and viewership of our customers’ services are growing so fast, they can no longer rely on a sample-set of thousands when they are dealing with billions,” said Dr. Hui Zhang, co-founder & CEO of Conviva. “Things have changed quite a bit since Nielsen assembled a panel of viewers to analyze television. Conviva’s all-screen census measurement approach provides a unique perspective for understanding the dynamic landscape of viewership, content consumption and user experience across internet streaming services.”

In North America, streaming viewing hours increased 174%.

Conviva found that Apple TV saw 709% growth in viewing hours over the first quarter of 2017, based on the dynamic nature of the market and Conviva’s customer base, outpacing all other devices by almost two times. During the same period, while total viewing hours on Roku devices saw a rise of 87%, its overall share of total viewing hours dropped by 3%.

Quality of the streaming experience improved in the quarter. There was a drop in the number of videos that failed to start. The bit rate of video rose 29%.