When you analyze a single keyword in Keywords Explorer, we always force update the results (and consume a metric credit), so the results you get in Traffic share by domains will depend on what Google gives us at that specific time:

It is also worth mentioning that this only happens when you analyze a single keyword.

For multiple keywords we are using data from cache, so there should be no changes in Traffic share % and domains listed in the report.

Related

Did this answer your question?