IELTS Writing Task 1: 'to' or 'by'

In IELTS writing task 1, you might need to use verbs like increase, decrease, rise and fall. These verbs can be followed by the words 'to' and 'by', but what's the difference?

Let's use these figures:
- Company profit in 2005 = £20,000
- Company profit in 2010 = £25,000

Now compare these sentences:
- Company profit rose to £25,000 in 2010.
- Company profit rose by £5,000 between 2005 and 2010.

It's easy: 'to' is used before the new figure, and 'by' is used to show the change. It's the same when you are talking about a fall.