This is actually one thing we are working on these days. We are busy reviewing the dashboards, but we will also add new analytics capabilities to measure monthly active users. As far as I know it will still take a couple of weeks until we are ready to release it, so stay tuned on more info on this!

Maybe you can share your own thoughts as what you would count as an active user? We see that the opinions vary a lot here. Some communities count a login already as an active user, while others even count a like or even a visit...

I personally think you can regard a user as active when they create a post. If you check the Success Dashboard, we there also show an (all-time!) activation funnel (bottom right corner). Here we have listed which activity levels we have defined:

You can actually also do a topic- and post-export of a month. Combine the two, create a pivot table to count the amount of content created per user. Then you can apply your threshhold of choice to see how many active users your community has seen this month.