Testing GTM-GA implementation with new property
I have created a new Google Analytics property and added it in GTM through the Google Analytics tag. Before removing the actual Google Analytics script, I wanted to test if the GTM implementation will give me the same data. Unfortunately, the numbers are different. I understand that New Sessions is bound to be different because of the absence of visitors history in the new implementation. However, sessions also have a difference of approximately 30,000, which is huge.
Possible reasons for the difference?
Re: Testing GTM-GA implementation with new property
How clean is your GA implementation? That is, are you really comparing apples to apples? Are you looking at only traffic coming from this host or is there significant referral spam? are you tracking any apps or other sites on the straight GA version?
Perhaps looking at the hostnames report (audience>technology>>network then select hostname as primary dimension) or pulling in hostname as a secondary dimension would help identify the source of the discrepancy.
Hope that helps.