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Source field values explained:
Q: Why is the Campaign Term populated with "(not provided)"?
A: In October last year Google implemented a change to "make search more secure". From this date users who performed a search whilst logged into a Google account would have their search query encrypted over the HTTPS protocol. Whilst the user experience has remained pretty much the same when searching, the owners of visited search results are no longer able to obtain information on the keyword which was searched - this now being reported as "(not provided)". More information can be found via this blog post.