Here's a list of possible metrics that we could use for measuring community health.

Introductory notes:
* I emphasized the number of unique contributors rather than number of contributions.
* All of these metrics can be calculated over a variety of time-frames, although I suggest monthly because that is our existing default for many metrics.

My suggested list:

* Number of new accounts created that are not blocked within 31 days
* Number of new accounts that make 1 edit and are not blocked within 31 days
* Number of new accounts that make 5 edits and are not blocked within 31 days
* Number of active editors
* Number of rolling surviving active new editors (see https://meta.wikimedia.org/wiki/Research:Rolling_monthly_active_editor)

* Percentage of active editors who self-identify as non-male

* Number of articles and files on all wikis that have passed quality reviews

* Number of volunteer publicly logged non-edit actions

* Number of contributors to all public mailing lists
* Number of contributors to social media discussions on all platforms
* Aggregate sentiment of all discussions relevant to Wikimedia on all platforms

* Number of unique senders of OTRS requests

* Number of unique responders to OTRS requests

* Number of files with OTRS permission tags

* Average wait time for resolution of OTRS requests
* Maximum wait time for resolution of OTRS requests

* Number of contributors to Phabricator
* Average Phabricator "unbreak now" task wait time to closure
* Average Phabricator high priority task wait time to closure
* Average Phabricator task wait time to closure
* Number of contributors to Gerrit
* Number of patches created
* Number of code reviewers
* Average patch code review wait time
* Maximum patch code review wait time

* Number of wikis with at least 100 unique editors active
* Number of wikis with at least 1000 unique editors active
* Number of wikis with at least 10,000 unique editors active
* Number of active admins on all wikis

* Number of files uploaded that are not deleted within 31 days
* Number of media files in use on wikis other than Commons

* Number of members of affiliates
* Number of volunteers of affiliates (this includes online and offline activities)

* Number of affiliate organizational partnerships

* Number of active affiliate organizations
* Percentage of affiliate funding from sources outside WMF

* Number of unique donors to affiliates
* Number of unique donors to WMF
* Number of repeat donors to affiliates
* Number of repeat donors to WMF
* Number of WMF organizational partnerships

* Number of active WMF grants

* Number of unique active WMF grantees

Additional comments:

Note that the Learning and Evaluation team independently seemed to be doing some work about relevant metrics on https://meta.wikimedia.org/wiki/Grants:Evaluation/Measures_for_evaluation in September 2014.

Finally, I would like to suggest that research about community development in general may be relevant to work on Wikimedia community health online. Suggested reading:

* https://en.wikipedia.org/wiki/Social_psychology
* https://en.wikipedia.org/wiki/Social_capital
* https://en.wikipedia.org/wiki/Community_building
* https://en.wikipedia.org/wiki/Community_development
* https://en.wikipedia.org/wiki/Community_indicators
* https://en.wikipedia.org/wiki/Community_of_practice
* https://en.wikipedia.org/wiki/Urban_planning
* https://en.wikipedia.org/wiki/Community_policing
* https://en.wikipedia.org/wiki/Sense_of_community
* https://en.wikipedia.org/wiki/Social_network

I hope that these suggestions help to move the community health conversation forward.

Pine