Netflix and YouTube dominate over half of downstream Internet traffic in North America, according to a new report released by Canadian Internet monitoring firm Sandvine.

Downstream traffic is data that goes from a source to a computer, and Netflix's share of that is 31.6%. YouTube comes in second at about 18.7%, up 9% from the first half of this year.

See also: 6 Great Alternatives to Netflix

The increased dominance of streaming services has also lessened the impact of peer-to-peer traffic and video piracy. BitTorrent accounts for around 4% of North American downstream Internet traffic, compared with 31% five years ago.

Statista's chart, which uses data from Sandvine's Global Internet Phenomena Report, shows which shares of U.S. downstream web traffic can be attributed to different properties.

The mobile numbers from Sandvine's report tell a bit of a different story. YouTube controls the largest portion of data, at nearly 17.7%. Facebook follows in a close second, about 2% behind.

Image: Mashable composite. iStockphoto, blamb, billnoll, BitTorrent, Netflix, YouTube

Zoe Fox contributed to this story.