Google Ads has introduced a new bid simulator, the Target ROAS bid simulator. The target ROAS bid simulator shows the relationship between a ROAS target and your key metrics. The key metric it shows is your conversion value.
Google explains; let’s say you’re interested in seeing how a higher target would impact your performance. Using data from the auctions you participated in over the last 7 days, this tool will show you what would have happened assuming everything else (e.g., your ads, landing pages, competitor ads, competitor bids etc.) stayed the same.
Here is a screen shot: