My forums have the same people visiting over and over again and it seems they have developed ad blindness. I mean, my CTR is just 0.4%. It's terrible. I've tried putting the ads on various places on the page but nothing seems to work. Do you have any suggestions?
CTR means click through rate. It increase when some specific link clicked by same people i.e.from same IP again and again. When click through rate increase then their effect directly shown on the PPC and CPC. To increase click though rate the must effective way is email advertisement. You can go for it.
You need to go with some digital marketing expert that relay help you in a getting more visitors for your website.
It's also help you in a increasing CTR (click through rate) after increasing ctr your forum it's automatically increase ppc and cpc.
It is tough to monetize the forums using Adsense as people won't click the ads because they knew they are advertisers.If you are getting visitors from Search engines also they won't click the ads all the time. Forums displays different type of ads while on blog it displays correct ads.
Forums get very low click through rate even from searchers. Try to blend the ads and place on different areas to see whether the CTR increase or not.
CTR increase when new visitor click on ad. But as you say you have a forum website. If you want to new visitor on your forum website then you have to must be apply some Search Engine Optimization technique. So you can increase your ad income.
Managing CTR is not so easy as it seems. Even it is noticed if no proper navigation or validation is made , CTR may not cover leads in advertisement. CTR, which stands for Click Through Rate is a mechanism which requires dedicated banner, or well designed skills and schemes that may attract other. You may take the look of your competitors website for the same not to cheat but to overcome and modify your ad banners or respective platform for CTR using high keywords, your featured products and other key resources that you have.
Track the current state of your click-through rate.
Focus on improving page titles.
Test page titles in order to pick the most effective.
Improve URL structure to make it descriptive.
Pay attention to your meta descriptions.
Make use of rich snippets and structured data.