NEW YORK — 43% of the national advertisers already engaging in influencer marketing plan to put even more money into it in the next 12 months, according to a study released last week by the Association of National Advertisers (ANA).

The study, based on a survey of 158 client-side marketers, found 75% of national advertisers currently use influencer marketing, with Instagram and Facebook the top social channels for deploying such initiatives.

Instagram was ranked the most important channel overall, with 36% of respondents saying it was their top platform for influencer campaigns. Facebook is favored by 20% of marketers surveyed.

The report also found brands hired a wide array of influencers — some with as few as 50 followers, others with more than 100,000.  Mid-level influencers, who have 25,000 to 100,000 followers, are currently the most popular with brands, 66% of which use them.

Nearly two-thirds, or 62%, of brands pay influencers, with the same number of companies spending less than $100,000 a year on the efforts. Thirty-five percent give influencers free products instead, the study found.

Whether that’s money well spent depends on whom you ask. A majority, 54%, of respondents said they were satisfied or very satisfied with the performance of their marketing. However, 39% said they are neutral on the subject, largely because they have not engaged in it long enough, or with great enough scale, to know. When asked whether their influencer marketing is effective, 39% of respondents said yes, 44% were neutral and 19% said no.