How much will be spent on mobile advertising through 2021, and what will be the sources (and destinations) of those dollars? These are questions we’ve answered in a white paper that publishes today.

Among the $72 billion projected for U.S. mobile ads in 2021*, search will continue to hold the leading share, but it will be slowly overtaken by native social advertising (i.e. Facebook News Feed Ads).

That and several other factors driving U.S. mobile ad spending are broken down in the free report**. You can also see the executive summary below, and a video breakdown in the clip embedded further below.

Executive Summary

Twice per year BIA/Kelsey devises a forecast that projects ad spending for location-targeted advertising. The five-year outlook comprises media such as television, radio, Yellow Pages, online/interactive and mobile — all covered in an extensive slide-based deliverable.

For the first time in report form, we’re now drilling down on one of those areas: mobile.* In addition to inclusion in the cross-media forecast, its growth and complexity compel standalone treatment. This report accomplishes that through data and narrative on mobile advertising’s many layers.

The findings: Mobile* is the fastest growing among all location-targeted media that BIA/Kelsey tracks. When panning back to mobile’s overall U.S. ad spend (local and non-local), it’s estimated at $33 billion in 2016, growing to $72 billion by 2020, a 17 percent compound annual growth rate.

Zeroing in on the location-targeted portion of that overall mobile ad spend, it will grow from $12 billion in 2016 to $32 billion in 2021, a 21 percent CAGR. That translates to 38 percent of overall mobile ad revenues today, growing to 45 percent by 2020.

Drivers include mobile users’ commercial intent and advertisers’ evolution to align with that behavior. There are also premiums associated with location-targeted ads — a function of their performance and growing demand. And Madison Avenue is latching on to these realities.

In addition to segmenting mobile ad spend by its locality, BIA/Kelsey breaks it down by format. There we see notable trending in revenue share between search, display, messaging, video and native-social. Search has long ruled but is slowly losing share to emerging formats.

Native-social ads are a notable component of this year’s forecast. They’re defined as in-feed socially targeted advertising in vertically scrolling interfaces (e.g., Facebook, Twitter, Instagram). Their growth follows millennial usage behavior and advertiser demand for content marketing.

These and other findings emerged through BIA/Kelsey’s all-year process of collecting, analyzing and synthesizing forecast inputs. The result is a data set that carries an eight-year legacy of time-tested accuracy and commentary on where things are moving next.

*BIA/Kelsey’s mobile calculations do not include tablets.

** This report is a free download, courtesy of Marchex.