If you have a blog hosted on Tumblr, you’ll simply love Tumblr Stats - it’s a free service that analyzes and displays some interesting statistics about your Tumblr based micro-blog. The service won’t ask for your Tumblr password so you may use it to study almost any public blog on Tumblr.
You just need to enter your Tumblr username and Tumblr Stats will display the total number of posts, post distribution (regular, photo, video blog, quotes, etc.), frequency of posting, and an approximate age of your blog.
Tumblr Stats uses the Tumblr API to analyze your blog posts and you are very unlikely to get this kind of data via Google Analytics or any other web stats software.