Got a reply from the Adsense team:-
This does sort of tie your hands ever so slightly....
Thank you for your email.
You are welcome to disclose information about your gross earnings with
AdSense. However, we ask that you please refrain from disclosing other
account information, including but not limited to, page views, number of
clicks, and your click-through rate.
We appreciate your cooperation.
For additional questions, I'd encourage you to visit the AdSense Help
Centre ( Google AdSense Help Center
), our complete resource
centre for all AdSense topics. Alternatively, feel free to post your
question on the forum just for AdSense publishers: the AdSense Help Group
( AdSense Help | Google Groups
The Google AdSense Team