Valentine Z posted a breakdown of nation categories by %:
I then followed by using the data from 2003 and comparing it to Val's trawl to see how things have changed:
I'm presuming the rise in ICDs is due to an increased use of puppet nations for non-stat dependent things (e.g. military gameplay) as ICD is the default state when not choosing any options.
What is more curious is the explosion of more radical nations, especially PDs and Anarchies.