Visits should NOT be part of a conversion rate because it takes different users different amounts of visits before they decide to convert. In other words, a visitor who converts after 20 visits is just as valuable as a visitor who converts on one visit. Ergo, the Conversion Rate in GA is not a fair statistic and would be enhanced by Goals Completed/Unique Visitors. How does that not make sense?
To answer your question, it's called a conversion rate. And it should not be based on the # of visits (as I explained above). It should be based on the % of individuals who visit your site and ultimately convert.
Sorry, I should have renamed the thread to "Goal Completed/Unique Visitors" I can see the confusion now.
I thought you wanted to have like goals (achievements) for how many visits you got. You never mentioned the word conversions. Well, every site has different views on what a conversion is. A conversion may be selling a producy, getting a new member, new reader to newsletter, being contacted by a visitor though forms and so on. What you're asking would require a lot of backbreaking coding to implement a feature that recognizes a conversion in every different form it may appear. Not only from google but also from everyone watning to use it. So after all I think it's best if you just do the math yourself. It's not that hard.
Well Conversion Rates in GA already rely on event tracking so the JavaScript code would not have to be changed. But Google Analytics decides to report Conversion Rates on the basis of visits. Wouldn't you agree that this is a poor way of measuring conversion rates? Based off this metric, two web sites can have completely different conversion rates but have the same success rate of ultimately converting unique visitors. In fact, under this example, the poorer conversion rate would be more favorable because it shows the visitor is coming back to your site for more of what you offer.
Avinash agrees with me ... http://www.kaushik.net/avinash/excellent-analytics-tip5-conversion-rate-basics-best-practices/