Whatever.
Personally, I find that looking at the number of new users, or the number of new topics, or any of those statistical metrics (except possibly unique page views) tells you very little about the health of a community. HLP is output-oriented, much more like one of those "Nexus" sites that cater to the needs of the modders rather than the players.
It's by the output we should judge ourselves, and I think that due to the overall rise in quality we've seen over the past few years, people are more careful with regards to what they put out. It's like the frantic creativity of the early days has given way to a more deliberate, more considered pace, which is a development I find hard to evaluate in one way or another. Pros and Cons, you know.
Personally, I think that with the rising interest in space sims (Star Citizen, Strike Suit Zero.....), it is only natural that we as a rather FS-centric site may be losing a bit of traffic to those newer, flashier titles.