The AdWords tool to show click, cost estimates, and impression "Bid Simulator" has now been upgraded with the inclusion of Conversion Predictions.
AdWords Bid Simulator displays estimates for 1-per-click and many-per-click conversions. The conversion Estimates feature will provide data on the basis of clicks from the recent seven days.
Conversion estimates are however limited to high volume keywords. Many AdWords users will see conversion estimates only for brand keywords. So, users may find the sparse conversion data not much helpful in making predictions about future performance.
The conversion data might be helpful in determining whether to test bids for the accounts that have high converting non-brand keywords.Google Adds Conversion Predictions to AdWords Bid Simulator!,