If a client hands their agency $100 to spend on advertising, how much of it goes to OOH?

In China, $9. In Brazil, $12. In South Korea, $8. In France, Australia and Italy, $7. In Japan, $6. In the UK and Germany, $3. In the US, $2 - the lowest share of any major market in the world.

This is WOO's 2025 data on the top 10 global OOH markets, measured two ways: total dollars spent, and OOH's share of total ad spend in that country.

Both numbers matter, and they tell different stories depending on which one you're looking at.

China leads on both counts: $18.2bn in OOH spend and 9% of total ad budget.

The US is the second-largest market by dollars ($9.5bn) but sits at the very bottom by share (2%).

Brazil is the smallest market in this top 10 by volume ($1.3bn) and the highest by share (12%).

Three very different shapes, three very different stories. How do they come together?

The share numbers complicate the easy story

The instinctive read is that rich, mature ad markets have diversified into digital and no longer need OOH, while less mature markets lean on it more.

Yet…

Australia is not a developing market. It's a wealthy, digitally sophisticated, English-speaking economy - closer to the UK and Germany on most measures than to Brazil. Yet Australia allocates 7% of ad spend to OOH, more than double the UK's 3% and more than triple the US's 2%.

Japan and South Korea complicate it further. Both are mature, dense, highly urbanized East Asian economies with world-class transit systems - about as close to twins on paper as this dataset offers. Japan sits at 6%. South Korea sits at 8%, closer to China than to its regional neighbor.

Three bands, but GDP isn’t the determining factor

Sorted by OOH's share of ad spend:

• Low (2–3%): United States, United Kingdom, Germany
• Mid (6–7%): Japan, France, Australia, Italy
• High (8–12%): South Korea, China, Brazil

South Korea, a developed economy by any measure, sits with China and Brazil rather than with Japan and Germany.

Australia and France sit together despite Australia's economy having more in common with the UK's than with France's.

Whatever is putting the US, UK and Germany in one group and China, Brazil and South Korea in another, it isn't simply how large or how developed the economy is.

So… what is this pattern actually consistent with?

Two things can explain why a channel's share of ad spend differs across markets, even when the channel itself is healthy.

First: how well a channel can prove it worked. OOH doesn't have a standard, comparable way to measure audiences across markets. Digital does. And more media-buying decisions now sit with digital-native agencies, where budget tends to follow the channels with the cleanest data. The US, UK and Germany are also the world's most digitally instrumented ad markets. It's not proof - three markets isn't a sample size that proves anything. But it is a pattern worth watching.

To say it more simply, a low share in the US, UK or Germany may say less about how well OOH actually performs there, and more about how hard it is to prove.

Treating share-of-spend as a performance signal, on its own, can mean under-investing in a channel for the wrong reason.

Second: the pie is growing faster in digital. A channel's share can shrink even if its own spend is fine, when everything else is growing faster around it. The US shows this clearly. OOH spend there has recovered to near pre-pandemic levels. But its share of total ad spend still dropped, from 3.6% in 2019 to 2.3% today. Why? Total US ad budgets grew faster than OOH did. The channel isn't shrinking. Its slice of a bigger pie is.

Where this leaves us

The band pattern is real. GDP doesn't explain it, and neither does a simple developed/developing story - Australia and South Korea are the clearest evidence of that.

What comes closer, is a mix of how digitally instrumented each market's ad-buying infrastructure is, and how much of the gap is genuine market behavior versus how each country counts the numbers in the first place.

Two questions follow directly from that, and they're both answerable with real numbers, not more theory:

• How is OOH inventory actually supplied against demand in each of these markets - is South Korea's 8% a function of scarcity, or genuine appetite?
• And, how much of each market's OOH spend is already digital versus static? A market buying mostly programmatic screens is playing a different game than one still selling static billboards, and that alone could explain part of the band split.

Will be digging more into this soon!

#WhatMovesPeople