You also need to state what the main trend or trends in the graph are. Don’t give detail such as data here – you are just looking for something that describes what is happening overall.
One thing that stands out in this graph is that one type of fast food fell over the period, whilst the other two increased, so this would be a good overview.
Here is an example:Overall, the consumption of fish and chips declined over the period, whereas the amount of pizza and hamburgers that were eaten increased.This covers the main changes that took place over the whole period. You may sometimes see this overview as a conclusion. It does not matter if you put it in the conclusion, but you should provide an overview in one of these places.