Dear Adsense Publishers, the base currency for most of us will be different that the Payment Currency by the Google Adsense i.e. US Dollar. Most of us would be willing to visit our Performance Report in our own currency rather that the default one, i do want to see the report in my Indian Currency i.e. Indian Rupee. And the Adsense team made it available for the Publisher around world to look at their Adsense Performance report in their own currency, hence they can estimate their performance. And i came to know about it by a post written by Mr. Miki Noda, Adsense Payments Specialist.
In the article Miki written that the team was hearing about this requirement from many publisher around the world. We can see a message in top of the reports section that the report would change day to day as the currency rate fluctuation and as well it will not effect your earning based on the default payment currency.