Digital advertising revenues reached a historic high of $107.5 billion in the US last year, according to the Interactive Advertising Bureau (IAB) and PwC US. This growth is attributed to the direct brand economy, brand storytelling through video and a narrowing gap between mobile usage and mobile advertising spend.

IAB presented its 2018 Internet Advertising Revenue Report on Tuesday, pointing out that full-year digital revenues grew 22 percent YoY and surpassed $100 billion for the first time. Digital usage is up 20 percent YoY, IAB observed, even though the digital audience only grew one percent YoY.

Among all formats, digital video experienced the highest growth in advertising revenue, jumping 37 percent YoY to $16.3 billion. Digital video on mobile devices reached $10.2 billion in 2018, an increase of 65 percent. In fact, more than half—63 percent—of digital video ad revenue was on mobile devices.

Mobile ad revenue accounted for 65 percent of 2018 internet ad revenues, growing 40 percent YoY to $69.9 billion. The gap between mobile time spent and mobile ad revenue closed from 14 percent in 2017 to eight percent in 2018.

“Mobile revenues continue to benefit from advancements in single-click eCommerce, creative ad formats and placements on social media sites,” said IAB in the report.

Social media revenue rose to $28.9 billion in 2018, an increase of 31 percent from $22.1 billion in the previous year. The company defines “social media” as advertising delivered on social platforms including social networking, social gaming websites and apps across desktop, laptop, smartphones and tablets.

“Consumers, especially Gen Z, are adopting social stories at warp speed, while, at this rate, we approach a future where social stories may surpass social feeds in becoming the prevalent way consumers engage with advertisements on social media,” says IAB.

IAB does not break down social media ad revenue by platform but notes that the 2018 report includes Snapchat for the first time.

“Social media sites tend to foster consumer interaction and during a time when capturing the attention of the consumer is so critical, it is no coincidence we are seeing social media drive revenue,” says the report. “Ripe with various formats primed to take advantage of future technologies, revenue derived from advertisements on social media sites is expected to continue to grow in the future.”

Overall, marketers are pouring more budgets into the internet than any other platform. Print media, however, was the only category to experience a drop in advertising market share. Newspaper ad revenue dropped 6.9 percent while magazines dropped 2.1 percent.

Digital audio advertising revenue grew 22.9 percent in 2018 and reached $2.3 billion compared to $1.8 billion the previous year. IAB will release a dedicated digital audio report later this year.