I opened Google Analytics website->Demographics->Overview and got following data of my android app:
There is a line at top right corner
71.12% of Total sessions
What does above line means to the data?
What about the remaining 28.88%?
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Sign up to join this communityIt's sampling. Google Analytics analyzes a sample set of data to extrapolate an estimate of 100% for certain non-default reports. This is common with most analytics tools as it saves huge amounts of space / CPU.
The thresholds for Google Analytics are thus:
Default reports are not subject to sampling.
Ad-hoc queries of your data are subject to the following general thresholds for sampling:
https://support.google.com/analytics/answer/2637192?hl=en
It is possible to get un-sampled data using the API but for most purposes, sampled data will still allow you to make actionable marketing decisions.
It means Google was able to identify the age of the visitor during 71.12% of your site visits