When your highly personalized Google search results are tailored to you and you then want to measure the performance of your own stuff, for the love of God don't use your own computer to look it up, if you appear on the first page, that might be because it's very relatable to your searches, the ones you used to research and create this stuff.

A first page result is absolutely no garentee that other people are going to see the same as you. And there is only one way to control what people search, social engineering.

So I think a better metric is, how many people did arrive on your site for a particular bit of content.