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Understand information in your reports and troubleshoot reporting issues such as self-referrals, (not set) data, and inaccurate information
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Number has unreasonable changes after segmentation

Visitor ✭ ✭ ✭
# 1
Visitor ✭ ✭ ✭

Hi Sir,


We found a problem about segmentation and users report. 

Please see below images, we used segmentation to find specific users.

I only changed the time period on upper right corner, you can see the number of 201603 changed a lot, from 8 millions to 10 millions. 



Anyone know the reason and how to explain it?






Re: Number has unreasonable changes after segmentation

Follower ✭ ☆ ☆
# 2
Follower ✭ ☆ ☆
Hi Ya-Ling,

This is probably due to how sampling is being applied to generate report faster when you hit 500k sessions as a standard user. Take a note of the yellow box below each date range filter.
The report for March (first report) is based off 1.14% of the sessions.
The report for February and March (second report) is based off 0.65% of the sessions.
Note that by doubling 0.65%, we are actually looking at 1.3% of total sessions per month, which is more than the 1.14% used in the first report. This tells us that we will probably have more traffic counted for the March report. In addition, February is a shorter month, so larger sessions of traffic are accounted for the month of March in the second report than the first.