There has been an 83% year-over-year growth in influencer marketing spend in the US and Canada, according to research from the influencer marketing measurement company, Instascreener.

Despite marketers like Unilever’s former marketing chief Keith Weed calling the industry out for ineffective measurement, fake followers and influencer fraud, spend on the medium is still on the rise.

Instascreener, formerly known as Points North Group, said it used third-party software that analyzed nearly every sponsored post on Instagram. For non-Instagram influencer spend, it used its own spend data and research to measure investment.

It found that the second quarter of 2019 was the largest quarter yet for influencer marketing, with brands spending a total of $442m. This was up by 18%, $69m, compared to the previous quarter.

In the second quarter, $314m was spent on Instagram but a total of $58m reached fake followers.

Fashion Nova was the top spender, ploughing $5.5m into social stars. This was closely followed by vodka brand Ciroc which spent $3.4m and Flat Tummy Co which spent $2.9m.

Although spending is on the rise, influencer marketing is still a particularly murky area which the Advertising Standard’s Authority (ASA) has been keen to clamp down on.

Earlier this year, the UK ad watchdog cautioned “between 200 and 300” social media influencers for breaking strict rules around paid-for posts on the likes of Instagram.

Fake followers also continue to be an issue. Last month, social media research laid bare the ITV show Love Island, showing that every contestant (with one exception) booted their Instagram influencer status by amassing an army of fake followers. According to the research, 50% of their purported followers were fake.

Despite this, recent research by Whalar ruled heavily in favour of the medium, finding influencers ads to be ‘more emotionally intense’ and memorable than TV ads and ads found on Facebook and Youtube.

The study claimed to be a “world’s first” neuroscience study on influencer marketing and found influencer ads to be 277% more “emotionally intense” than TV ads.