YouTube continues to obliterate completion and keeps on growing. It is always the best online video website. In May, 176 million Americans watched at least one video online and, on average, each viewer watched almost 16 hours-worth of videos on the web.

“176 million U.S. Internet users watched online video content in May for an average of 15.9 hours per viewer. The total U.S. Internet audience engaged in more than 5.6 billion viewing sessions during the course of the month,” comScore reported.

“Google Sites, driven primarily by video viewing at YouTube.com, ranked as the top online video content property in May with 147.2 million unique viewers, followed by Vevo with 60.4 million viewers and yahoo! Sites with 55.5 million viewers,” the report detailed.

“Facebook.com came in fourth with 48.2 million viewers, while Viacom Digital ranked fifth with 46.5 million viewers,” it added. In total, 147 million people watched a YouTube video, while only 60 million watched a video on Vevo, the runner-up.

Yahoo is the first real competition to YouTube, but it is very far behind with just 55 million viewers and 272 million views. Facebook is following closely with 48 million viewers and 176 million views.