ZenithOptimedia has released its latest advertising expenditure forecast, predicting that global ad spending will come in at $524 billion by the end of the year, an increase of 5.4% over 2013 numbers.

This forecast is very slightly downgraded from the agency’s last report, which came out in April, and predicted that global ad spend would grow by 5.3% for the year. The downgrade comes largely because of the widening conflict in Ukraine and economic sanctions in Russia both dampening the global market.

North American ad spend is expected to grow at a rate of 4.7% for the year, boosted by events like the Winter Olympics and mid-term elections. That is over last year’s growth, which came in at 3.5%.

Global ad spend:

Internet advertising remains the fastest-growing medium, with average annual growth predicted to come in at 16% for each year between now and 2016. ZenithOptimedia includes

The platform is being driven largely by display, which is the fastest-growing sub-category, with 30% growth a year, according to the report. That includes traditional display like banner ads as well as online video and social media.

Resources are being put into investing in research that should measure consumers’ exposure to traditional display ads more accurately and also to track exposure across multiple platforms, including desktop computers, tablets and TV screens. In addition, some broadcasters are starting to trade packages that include both online video and TV spots.

ZenithOptimedia forecasts online video to grow at an annual rate of 24% for the remainder of the forecast.

Mobile internet advertising is expected to grow at a rate 5.5 times faster than desktop internet globally, boosting by an average of 49% annually between 2013 and 2016. By contrast, desktop internet is expected to grow at a rate of 9% a year.

Globally mobile is expected to contribute 38% of all extra ad spend between 2013 and 2016, ahead of TV, which is expected to introduce 31% of new ad expenditure to the market.

Here is how ZenithOptimedia sees the share of each platform being divided out, in 2013 and looking forward to 2016:

Image courtesy of Shutterstock

Note: Canadian ad spend numbers were not updated in this report, but ZenithOptimedia says they will be for the next version, which comes out in September.