Whether you are using a great PPC optimization solution like Finch or not, one thing that is absolutely essential to measure when doing online advertising is what revenue or value you are getting for the money you are spending. The most common way to do this is to implement some sort of conversion tracking on your website. In order to optimize our client’s accounts, Finch’s automated PPC tool looks at conversion tracking information from AdWords, including Google Analytics goals that are imported into AdWords.

There are a number of differences in conversion tracking between Google Analytics and AdWords, many of which Google has outlined here. Because of these and other differences, the conversion numbers from AdWords and Google Analytics for the same website rarely match exactly. One important difference not mentioned in that article, but mentioned in various blogs and support forum posts, is that Google Analytics attributes a conversion and its associated value to the day that the conversion occurs, while AdWords attributes the conversion and its value to the day of the last AdWords ad that was clicked by the user. If the user converts on the same day that they clicked on the AdWords ad, then things can appear the same. However, people will frequently come back at a later date after clicking on the ad in order to make their purchase, in which case you will see a difference in the AdWords and Google Analytics UI for the conversion numbers on those days.

When you think about why Google does this differently in their two tools, it does seem to make sense. The purpose of AdWords conversion tracking is to measure ROI on your AdWords ads, so recording the conversion alongside the click of the AdWords ad makes it easier to directly see the results of the spend on that click. On the other hand, Google Analytics is measuring the results of visits to your website, so attributing a conversion to the day of the visit on which the conversion occurred is a reasonable thing to do.

One aspect of this that we have not noticed anyone writing about (including Google) is what happens in this respect when Google Analytics goals (in this case, conversions) are imported into AdWords. As mentioned above, the two tools can attribute the same conversion and its value to different days, so when AdWords imports Google Analytics conversions, one might wonder (as we did) who wins, so to speak. Does Google import the Google Analytics data as-is, or does it perform some translation in order to report conversions the way the AdWords documentation says its conversion tracking works?

What we have noticed with our clients is that, at least at the time of this writing, Google translates the Google Analytics conversion tracking when imported into AdWords so that it matches AdWords’ way of attributing conversions to a particular date. When drilling down to the details of conversions from individual keywords both in AdWords and Google Analytics, we have seen many cases of a conversion occurring from a PPC ad for a given keyword showing up in the Google Analytics UI on a particular date, but showing up on the (earlier) date of the ad click in the AdWords UI after it is imported.

This is nice functionality from our perspective, as it means that taking conversion lag information into account as Finch does its Google AdWords optimization is the same, whether the conversions are being tracked in AdWords directly or being imported from Google Analytics. If you are not familiar with conversion lags and are not paying attention to them, see our FAQs here.