There is no corresponding dip in our own traffic graphs. It is probably an Alexa measurement artifact. We started using a CDN and switched to https by default for logged-in users sometime in 2013, which could affect measurements.
As shown in the link, the traffic to HN dropped considerably in early-mid 2013 until it regained traction later in that year. Does anyone here have any explanation for that sudden drop in 2013?
