Marketers will shell out $100 million more on local radio advertising this year, taking the industry to $14.2 billion in local revenue, up from $14.1 billion in 2016. But the real growth will come in digital dollars, which are set to rocket up 17%, or $200 million, to $1.4 billion in 2017 from $1.2 billion in 2016.

The new numbers are from BIA/Kelsey’s Outlook For Local Advertising report, set to be released next week.

“Even with increased audio competition from many different sources, radio is still a formidable advertising platform, gathering over 10% of local adverting dollars,” BIA/Kelsey senior VP and chief economist, Mark Fratrik, said this week during a webinar presented by the Media Financial Management Association.

Looking ahead to 2018, radio’s combined over-the-air and digital assets are expected to cordon off 10.2% of the $155.6 billion that marketers will spend on local advertising, or $15.87 billion. The lion’s share will go to over-the-air radio, which is forecast to capture 9.2% of local ad dollars with another 1% coming from radio’s digital assets. “There will be some benefit from political advertising for radio in 2018 but not huge,” BIA CEO Tom Buono said.

Regionally speaking, radio’s share of wallet will grow faster next year in the Southeast (+1.1%) and the South (+1.1%) than in the West (+0.9%), the Midwest (+0.7%) and the Northeast (+0.5%).

And there are dramatic differences in growth rates from local market to market. For example, Boise will grow at a compound annual growth rate (CAGR) of 1.6% from $25.2 million in over-the-air revenue in 2017 to $26.9 million in 2021. But Pittsburgh will inch up only by a CAGR of 0.4% from $85 million to $86.3 million over the same period.

“There are wide variances from market to market but typically radio gets 10% to 15% of local advertising,” Buono said.

Looking out to 2021, radio’s local ad forecast calls for modest 2% gains each year to $16.2 billion in 2019, $16.5 billion in 2020 and $16.8 billion in 2021. But radio’s digital dollars will expand at a much faster double digit clip, up 12% to $1.8 billion in 2019, before increasing 5% to $1.9 billion in 2020 and surpassing the $2 billion mark to $2.1 billion in 2021.

“Radio will remain a prominent player; we’ve got it fifth out of the top media platforms,” Buono said.

The new BIA numbers show radio’s share of local ad spend also varies from category to category. For instance, radio is forecast to over-perform in nationwide finance and insurance spending. Over-the-air will siphon off 13.1% of local media dollars in this key vertical while radio’s online properties will grab another 1.5%. That amounts to more than $2.5 billion spent on radio from the likes of GEICO, State Farm and local banks and other financial institutions. Only direct mail (28.8%) and mobile (19.9%) will attract a larger share of finance/insurance spending. “Radio gets a good share of that, more than 14.5%,” Fratrik said. “Radio is a really strong player in this vertical.”

The BIA outlook shows total industry revenue is highly concentrated in the largest markets. Of the hundreds and hundreds of radio markets, both rated and unrated, the top 50 will capture more than half of all radio ad spend in 2017. The top 10 markets alone will bag 25.7% of radio dollars, markets No. 11-25 will attract 13.7% and markets No. 26-50 will get 11.9%. The remainder will be divvied up among markets 51+: 10.3% for No. 51-100, 11.9% for No. 101+ and 26.9% for unrated markets.