Joomla!Days are events held in various countries where Joomla enthusiasts gather to learn, socialize and network. The first Joomla!Day was held in The Netherlands in 2006 and to celebrate the 7th get together which is being held in May, the organisation behind the event has produced a historical Infographic. It's interesting to see how the event has grown, not just in The Netherlands, but worldwide.
One fact that stands out is that female participation seems to mirror the IT industry in general. Come on girls! We need more female Joomla fans.