Duncan MacNiven: Surprise that arrived on our shores from the east

But perhaps the biggest surprise to me in my time here has been the way Scotland's population increased after the UK, Sweden and Ireland opened their borders to eastern European migrants when they first joined the European Union in 2004.

We didn't realise how much that would point them in the direction of Scotland. Instead, we'd thought: "Ah, Germany is closer, they'll go there."

When I was appointed in 2003, Scotland's population was 54,800 over the five million mark, and had been going down since 1974. So, I'm leaving the job with numbers up, to 5,222,100, something I'd never have imagined.

The other surprise for me has been the upsurge in the birthrate for Scottish mothers. Part of it, at least, is because women were postponing having children.

While my MA in history from Aberdeen University and an MLit on the merchants of early 17th-century Aberdeen might not sound like preparation for looking at detailed statistics, they were, in fact, good preparation for working as a civil servant, by giving me experience of finding out facts, speaking to people and summing up the main points.

Despite having all the information to hand, one of the first things I'm going to do when I have more free time is to work on my family tree. I'm a keen hillwalker and finished climbing all the Munros in 1983. I might do them again, but this time in better weather.

•Duncan MacNiven is the Registrar General for Scotland