PolitiFact’s Obameter combines old-fashioned beat reporting with online structured data to create a Web-based catalog of President Barack Obama’s 2008 and 2012 campaign promises. We define a promise as a guarantee of prospective action that is verifiable. Our reporting documents what has happened to the promises after the campaigns ended.

Eight years, 533 promises and countless hours of reporting later, PolitiFact has amassed the most comprehensive database of presidential power ever assembled.

Like PolitiFact’s fact-checks, each promise is assigned a rating with a report that explains why we rated it the way we did. A promise fulfilled, or largely fulfilled, rates Promise Kept. A promise not fulfilled rates Promise Broken. And a rating of Compromise is assigned to outcomes that are substantially less than the original pledge but still achieve something significant consistent with the goal. Prior to our final judgment, promises can be rated In the Works, Stalled or Not Yet Rated.

We rate promises based on outcomes, not intentions. If Congress blocks Obama’s pledge, it rates Promise Broken. We decided on this method after realizing it would be impossible to rate whether a politician intended to keep a promise or put in enough effort.