AdSense Revenue Down 30-40% After Using Responsive Ads ?

Our team has a WordPress blog website which built in 2007 or more earlier. There are totally 770+ public text blogs (long articles or short message records) and 100+ private blogs on the site. However we did not spend enough time and enough enthusiasm to write good quality articles, so the monthly AdSense revenue was on low level.

We have gotten some spare time since the holiday season of 2015 to start updating the blog site, we changed theme using the newest WordPress official released theme named Twenty-Sixteen,  and we modified the theme ourselves a bit to have current UI. At least, the new theme supports both of desktop and mobile platforms, this was the major reason why we wanted to update the blog site.

The screen shot below is the OLD blog theme:

The following are what we are improving the blog website:

1: Updated WordPress to newest edition;

2: Updated the theme using newest theme to support mobile and desktop platforms;

3: Replaced most of classic AdSense ad units with Responsive ad;

4: Adding good quality articles daily;

5: Modifying existing article, to make them better quality daily;

However, we saw the monthly revenue dropped too much and happed right away. Even our revenue has already been a small amount, but compared to old revenue, now it is at least 30% or 40% down or more.

Below is the new UI:

We can not find out the exactly reason currently, but we are trying to contact Google AdSense support or get help from AdSense forum.

We will come back to share more information if we have in the future.