Google quietly announced on Google+ a new AdWords metric available in Google Analytics named Return on Ad Spend (ROAS).

Return on Ad Spend (ROAS) is a metric that tells you how much revenue you bring in for each dollar spent with AdWords. For example, if you earn $7 for each $1 you spend on AdWords, your ROAS would be 700%.

AdWords also lets you select a bid strategy based on ROAS, it is called Target ROAS.

Google said:

Forum discussion at Google+.