Since when is 215 + 193 = 404?
Here is an example of real Google Analytics data:
On January 31, there were 193 users coming to a clients website. On February 1, there were 215 users. If you add up both those numbers for a 2 day span you get 408.
However, when you put in the dates January 31 thru February 1, Google Analytics returns 404 users for the same period. Why is that? How did they miss 4 users?
Which numbers are correct? It depends on the time period needed.
Remember, the Users metric calculates the number of unique users coming to a website for a specific period.
In this case, during the 2 day span, 4 users came to the website on BOTH DAYS. Therefore, even though each came to the website twice in the 2 days, each only had 1 of their visits were counted as a UNIQUE visit.
Rule of thumb… when you want to count the number of users in a certain time period, use the exact date range for that period and not sum up each day.
Additional NOTE: Although the user wasn’t counted in the User variable on the 2nd day, the rest of the data was counted…ie Pageviews, Number of Sessions, Sessions per User…etc.