I'm not very active on the site anymore. I recently came back a bit, and was a bit puzzled.
Most of the metrics look fine, but the answered-question ratio is down to 75% - which is much lower than it used to be during my active time here. I think we never actually went below 80% during the first year. I had a quick look at the questions without answers - and they look, at a first glance, fine. My first guess - low quality easy homework questions causing this - doesn't seem to be necessarily true.
This metric needn't be bad. For example, if this comes from a larger user base and more representation of small fields with little activity, it's quite natural that very specific niche questions are less likely to be answered.
So, the first step should be gathering more data.
If you used to answer questions, but are doing less so today - what's the reason?
If you only contributed with questions and not with answers - why is that so?
I'll start with myself: I used to answer questions a lot, but a combination of less time, and an increase in the uninteresting-to-interesting ratio of question made me stop participation in this site alltogether somewhere in the beginning of the past academicyear.