Look at the picture and learn the vocabularies used. Here is the link belajar-ielts.blogspot.com/2014/05/look-at-picture-and-learn-vocabularies.html
1. Rose/ increased steadily
2. Rose/ increased dramatically
3. Rose/ increased gradually
4. Plunged to ...
5. Peaked at / reached a high of ...
6. Stood at
7. Fluctuated
8. Fell/ dropped dramatically/ sharply
9. Reach a trough of ...
10. Remained constant/ unchanged/ stable at ...
11. Levelled off/ evened out at ...
12. Hit a low of ...
It is held in 24th of May,
The best way to go about this task is to follow a solid essay structure and improve your time management skills on writing. If you have the essential features with good grammar and vocabulary, then you would be up on the deal.