I run a few blogs on topics like programming, linux tips and network security.
I noticed the following:
Till last year had only 1 blog that had posts on PHP, linux tips, network security etc. The AdSense RPM was around 1.00.
Then I split the content into 3 separate blogs, one focused on web development/PHP/MySQL. second one focused on Linux/Windows how-tos and tips and third one focused on network security and related network topics.
The Adsense RPM rose significantly for 2 blogs, and was 1.38 (PHP blog), 0.87 (tech tips blog) and 1.90 (network security blog).
In the month of april 2013 the site on network security had the highest traffic and the Adsense income of that site was twice that of all three sites combined previously.
My question is simple, does focusing on one topic lead to higher CPC/CPM?