6/1/18 UPDATE: And just like that, the data is back. Reports (as well as my own account) indicate the data is currently populated until 5/30. The data typically runs about 2 days behind in my experience, so it seems the issue is likely resolved.
This Monday’s Memorial Day (US) holiday and its extended weekend was accompanied by many reports of missing data in Google’s Postmaster Tools. In my own account (as in most of the reports I’ve seen) the data stopped rolling in on May 24th. Unlike some previous instances, all GPT data appears affected – Spam Rate all the way down through Delivery Errors.
Each time this happens, many of us hope it’s the oft-promised Postmaster Tools update – the one that brings API access, flexible dashboards and other as-yet-unannounced Google Goodness™. Thus far that hope has been unrealized….but there’s always next time. In the meantime, we’ll just stick to hoping Google restores the missing data in a timely fashion.