Five leading OTT services - Hulu, Peacock, Discovery+, HBO Max and Paramount+ - generated $1.3 billion in 2021 ad spending, according to MediaRadar, an ad intelligence platform.

MediaRadar also found that 5,530 advertisers ran ads on the 5 services and it calculates that spending on these streaming services accounts for just 3% of total digital ad spending per month.

YouTube, which reported nearly $29 billion of ad revenue globally in 2021, is clearly the 800-pound gorilla of the industry and isn’t in MediaRadar’s universe (but note a lot of YouTube’s ad revenue comes from outside the U.S.). Two other big players, The Roku Channel and Amazon also aren’t counted in MediaRadar’s report.

For a little context, at VideoNuze’s CTV PREVIEW: 2022 last month, eMarketer’s Ross Benes provided an estimate for 2021 U.S. ad revenue of $14.5 billion, with the top 5 players accounting for 60% of the total.

Of the top 10 advertising categories spending on streaming (which collectively represent 81% of spending), Retail, Media, Tech and Finance were all about even, at around $150 million. The next 6, led by auto were all in the $50-70 million range.

MediaRadar also noted that “house ads” for promoting specific shows within a streaming services typically account for 12-15% of ad inventory, though for Peacock it was 30%.

Ad loads also varied widely, with Paramount+ carrying 17 ads per show, or nearly 24 per hour. This contrasted with Peacock which carried 4.6 ads per show, and 8.7 per hour.

There is a lot more data in the full report which can be downloaded here.