That's not typical of your car Robin.
http://www.fuelly.com/car/audi/a1/2011I see you're Welsh(or at least living there), Perhaps you're using imperial MPG in your post? http://en.wikipedia.org/wiki/Imperial_MPG
I'm using american gallons. Multiply your figures times 0.83 to get american gal.
In imperial gallons, my figures are 60-66 MPG-imp.
If you were using american gallons, here are some substantive things that probably offer a difference or two in our relative inefficiencies:
I live in the southeastern US (Atlanta, GA), which is basically a sauna for 150+ days a year (today is 82% humidity, with a "Feels like" temp of 37 C/99 F), so constantly run the air (which is actually more efficient than opening the windows for my particular car, a 2005 Toyota Prius).
The Audi A1 is a mini-cooper sized car (which my wife has). My car (a prius) is a mid-sized sedan (comparable in size to a Ford Fusion, which gets 22 MPG City/32 MPG highway). You can easily fit 2.5 as "person" and 4x as much stuff in my car as you can hers.
I take very short trips (living in Midtown, which as it sounds, is in the middle of town), so the engine is only at maximally efficient thermal profile for a short part of the time.
My car is actually 6 years old (although newer models don't really have higher overall MPG it seems). But to someone from 1995, my 2005 Prius getting 52 MPG would seem strange indeed, seeing 27 MPG in the city and 34 MPG highway was typical gas mileage for a 1995 Nissan Sentra, a popular midsized car of that year.