So, lets summarise. Full-time employees (full-time means at least 30 hrs a week) earn on average as follows:

1. Average hourly wage:        £12.76
2. Average weekly wage:     £506.00
3. Average monthly wage: £2,208.00
4. Average annual wage: £26,500.00

The above stats come from the Office for National Statistics. Here. Except number three above which I've extrapolated from the other figures. It might not be exactly right - but it's right enough for us.