In February 2013 I reported that the number of tweets by government agencies and councils had reached one million in January of that year, and eleven months laters in November 2013 I reported that the number of tweets had exceeded 1.5 million.
At the time I predicted that it would take a shorter time to reach two million tweets from 1.5 million than the eleven months it took to reach 1.5 million from one million. I then predicted that the two million tweets level would be reached around 2014.
I was half right. It was faster to reach two million tweets - taking only ten months - however by my count it wasn't reached until this month, September 2014.
Given I'm sure I've missed a few active accounts, and I excluded deleted and decommissioned ones, I'm comfortable with a two month margin of error.
Many of the numbers numbers have more than doubled since January 2013. Agencies are tweeting three times as frequently and the total number of followers has increased 2.22 times.
You can view my raw figures and analysis in my Google spreadsheet and I'll provide more information and analysis in coming weeks.