Unexpectedly my earning increases 40% since a weak

Though the page impressions and page CTR are same

[dr_rizwan]

Unexpectedly my earning increases about 40%.

Since a week I have noticed that my earning is suddenly increased 40% though the page impressions & Page CTR are same but Page eCPM increases about 45%

I have also noticed that G is displaying more image add than text add.

Any body can explain why my eCPM and earning increases unexpectedly?

[Marcia]

Maybe it could be a seasonal flux?

[jahfingers]

New adwords CPM campaigns possibly.

[hyperkik]

Google implemented some significant changes to the program early last week, and a number of people have noted a significant increase in eCPM since that time. I would venture that the changes to the program are the cause of the increase.