It’s a digital world, but when researchers look to where emerging markets are making a growing impact on information exchange, their eyes are drawn to printed publications. Newspapers, magazines and other dead-tree matter are the fastest-growing source of information exchanges from emerging markets to wealthy economies, according to a new study funded by the global shipper DHL.

Most printed matter is exchanged between wealthy economies, and the trade is driven by language and region—so it’s no surprise that some of the biggest exchanges are between Canada and the US, or Germany and Switzerland.

But, since 2005, emerging market exports of printed matter to advanced economies have grown significantly, from less than 10% to almost 20% of global volume.

Why is this? Business professor Pankaj Ghemawat, who co-authored the study of global connectedness that returned this surprising result, says it’s tied up in human migration—and entertainment. Ghemawat says he himself is a part of this statistic because, like many other Indians living and working abroad, he subscribes to Bollywood film magazines.  The story is not so different for other emerging markets with plenty of emigrants and a thriving culture that expatriates want to stay connected with.

For an example, he points to the Indian and Chinese film industries. While the latter outstrips the former in terms of domestic box-office, both are tapping into audiences outside of their countries. This map shows countries drawn to scale by their share of Chinese film revenue:

China’s film industry is mainly regional.

This shows a similar breakdown for India’s film industry, just focused on foreign revenues, so India isn’t drawn to scale. You can see that Indian films travel better than China’s, with a greater share of foreign revenues coming from the US, the UK, and the Middle East than nearby countries:

India’s film industry garners more of its revenue abroad than China’s.

Where those films end up, magazines aren’t far behind—and that’s just one aspect of the cultural business that follows migrants abroad when they move for work or study. China to the US, for instance, is the second-largest publication trade flow in the world, thanks to many Chinese immigrants and students.

But as Ghemawat notes, we’re still not all that linked: Only 25% of the world’s traded print matter are coming from emerging markets, with 75% coming from wealthier countries. Just as with telephone call volumes, measuring the changing flow of knowledge around the world gives us a window into just how interconnected we are—and how much further we have to go.