The Australian Bioinformatics Network kicked off on 1 July 2012, nearly two years ago.
Here's how it has grown since then:
This chart shows cumulative membership of AustralianBioinformatics.net and cumulative active membership the ABN Yammer. Alas, they are updated manually, and the membership of ABN.net lists some duplicates and dormant accounts. Still, they give us a sense of how things are growing.