To answer your question, although Pinterest is still in the 'coming of age' part of it's existence, there are a few different ways to measure the analytics and ROI generated from Pinterest. I use the following:
To measure base analytics like bounce rate, likes, pins, page views etc, I tend to use Pintics and Pinerly, http://www.shopinterest.co//
To measure ROI via Pinterest, I use Pinfluencer. Great great ROI tracker. http://www.pinfluencer.com/
Hope that helps,
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