paying member resulting from the price increase on our most popular streaming plan and the introduction of the premium plan, offset partially by the impact of exchange rate fluctuations. Average paid international streaming memberships account for 27% of total average paid streaming memberships as of December 31, 2014, as compared to 20% of total average paid streaming memberships as of December 31, 2013.

The increase in international cost of revenues was primarily due to a $311.5 million increase in content expenses including content for our new markets as well as more exclusive and original programming. Other costs increased $60.3 million primarily due to increases in our streaming delivery expenses, costs associated with our customer service call centers and payment processing fees, all driven by our growing member base.

International marketing expenses for the year ended December 31, 2014 increased as compared to the year ended December 31, 2013 mainly due to expenses for territories launched in the last twelve months.

International contribution losses improved $114.5 million year over year, as a result of growing memberships and revenues faster than content and marketing spending. Our International streaming segment does not benefit from the established member base that exists for the Domestic segments. As a result of having to build a member base from zero, investments in streaming content and marketing programs for our International segment are larger initially relative to revenues, in particular as new territories are launched. The contribution losses for our International segment have been significant due to investments in streaming content and marketing programs to drive membership growth and viewing in our international markets.



The increase in our international revenues was primarily due to the 134% growth in the average number of paid international memberships.

The increase in international cost of revenues was primarily due to a $272.0 million increase in content expenses. This increase was primarily attributable to continued investments in existing and new streaming content including content to support the launch of our service in the Nordics (launched in the fourth quarter of 2012) and the Netherlands (launched in the third quarter of 2013). Other costs increased $27.0 million due to increases in our streaming delivery expenses, costs associated with our customer service call centers and payment processing fees, all driven by our growing member base.

International marketing expenses for the year ended December 31, 2013 increased as compared to the year ended December 31, 2012 due to our expansion in the Nordics and the Netherlands offset partially by a decrease in spending in other territories.

International contribution losses improved $114.8 million year over year, as a result of growing memberships and revenues faster than content and marketing spending.

Domestic DVD Segment

In the Domestic DVD segment, we derive revenues from our DVD-by-mail membership services. The price per plan for DVD-by-mail varies from $4.99 to $43.99 per month according to the plan chosen by the member. DVD-by-mail plans differ by the