Google has made changes in the 30-day conversion window in AdWords by letting advertisers customize their window from 7 to 90 days.
This is a significant change for marketers whose sales cycle is longer than 30 days after an ad click and for those who are focused on getting repeat buyers back to the website & want to track their performance on this metric.
For advertisers who don't want the lagging conversions to impact their attribution, shortening of the window feature is also available.
The selection of the duration can be made by navigating to the Conversions tab present under Tools and Analysis. AdWords also provides a link to Search Funnels conversion time lag report that shows the time customers take for completing a conversion after they click on an ad.Google Lets Marketers Customize AdWords Conversion Window Settings from 7 to 90 Days!,