Soheil Bakhshi from http://biinsight.com has a super good article on how to get your stats from a WordPress site/blog and analyze them in Power BI.

For lazy guys out there, he already built a Power BI template file that you can use straight away. The only thing you’ll need is WordPress API key but don’t worry, he explains how to get that one too!

Check it out: http://biinsight.com/analyse-your-wordpress-blog-stats-in-power-bi/.