In order to increase your return on investment from online marketing, tracking is essential. By using tracking you can determine exactly which marketing sources are generating you sales or leads and then allocate budget and optimise accordingly. Unfortunately, tracking can be one of the most frustrating things to deal with online, with constant issues and parts breaking, not to mention that most tracking programs, whether internal or a third party, do not always exactly match each other.
Two of the most common ways to track conversions and traffic is Google Adwords and Google Analytics. Despite both services being offered by the same company there are huge differences in the way they track traffic, which most people are not aware of.
Conversions vs Goals
The most common way to calculate your ROI from your marketing efforts is through conversion tracking, which is measured differently through both Google products mentioned above. Other than the name (goals vs conversions) one of the main differences is the attribution model used. Google Adwords measures a conversion as anyone who has clicked an ad and then converted within 30 days. Google Analyics however, measures the conversion and then looks at the last traffic source and allocates the conversion to that source, whether or not they have clicked an Adwords ad in the last 30 days. Measuring traffic sources on two different attribution models can lead to inaccurate numbers of conversions being counted. For example, if a user clicks an Adwords advert, then a week later comes back to the site directly and converts, this would get counted in Adwords as a conversion but in Analytics this would be counted as a direct conversion. The date that these conversions are recorded can also cause confusion, with Google Adwords reporting the conversion as the date of the click, and Analytics reporting the conversion as the day the conversion itself occured.
One-per-click vs Many-per-click Conversions
By default, Adwords shows conversions using one-per-click metrics which means that for every click only one conversion is counted. Analytics however, shows data using many-per-click, meaning people can convert in a number of ways on the website and still be counted. For example, if a user clicks an Adwords advert and buys a product on the website, then also fills out a quote request form this would get counted as one conversion in the default Adwords settings, but two goal completions in Analytics. It is possible to add new columns to Adwords, which shows the ‘many-per-click’ metrics so this difference can be easily solved.
Clicks vs Visits
Clicks vs visits, one of the most commonly viewed statistics in both Adwords and Analytics are different by name and definition. The main difference is that the same visitor can click multiple (or the same) ads and therefore have multiple clicks in the Adwords statistics, but only one visit in the Analytics statistics. Adwords counts each and every click made, whereas Analytics counts visits which are defined by a 30-minute period in which the browser window is not closed. This difference can lead to an inflated number of clicks which need to be paid for vs the number of visits in Analytics, which appear to be generated from Adwords. Another reason that the numbers can be different is ‘Invalid Clicks’. These are clicks which are made by robots, are made fraudulently or have been identified by the Adwords team to be invalid. In Adwords these clicks are automatically filtered out of all results with a ‘credit’ for the cost of these ads given at the end of each month. In Analytics however, all clicks are tracked and counted whether invalid or not.
Javascript & Cookie Issues
Other than actual tracking errors, there are also a number of issues which will cause tracking differences. One of the most frequent issues involves visitors that have their Cookies or Javascript disabled. These visitors will not be able to load the Google Analytics code, so in Adwords the clicks or conversions would be counted but in Analytics these visits and conversions would not appear. The load time and position of the Analytics tag can also have an effect. If someone clicks an advert but then hits back before the Analytics code has had time to load they will again be counted in Adwords but not counted in Analytics, causing discrepancies between the two programs.
Errors
There are hundreds of errors that can occur with both Adwords and Analytics tracking, each of these has the potential to cause huge discrepancies and can be hard to identify. Some of the common errors I see is the gclid parameter being stripped on redirect, cookies lost on cross domain websites, auto-tagging not enabled in Adwords, Adwords and Analytics accounts not linked and many other errors.
Despite the fact there can be large discrepancies between Adwords and Analytics tracking, they are still two of the best offerings available. When preparing reports it is important that matching data is used so as not to inflate conversions, and for this I suggest using Analytics. Ideally, we would have perfect data, however this is near impossible so the key is to understand the data available and use it effectively to increase your ROI.