March 2016 - IRIS v4.0 Released (current version)
Immaterial change. Minor revision to definition language for clarity.
March 2014 - IRIS v3.0 Released
No changes. Minor revision to definition language for clarity.
November 2011 - IRIS v2.2 Released
February 2011 - IRIS v2.1 Released
September 2010 - IRIS v2.0 Released
New metric. Volunteer Hours Worked (OI1166) developed via IRIS Taxonomy Development Group.