Google posted an indexing issue with Google Search, saying it is investigating reports of indexing delays for content. Google posted, “Google is investigating reports about delayed indexing in Google Search that’s affecting a small number of sites. The reports of these indexing issues started to come in around 1:30 am ET on Thursday, December 21. Google said it is only “affecting a small number of sites.” Google will update us when it figures out the “root cause” of the issue. If you are noticing issues with indexing of your content and thus traffic issues to your site from Google Search, then this may be why.