The IELTS academic writing task 1 often asks students to interpret trends in charts and graphs. To get a good band score you will need to use specific advanced vocabulary. Here are some words and phrases that you can use to talk about rise and fall. The advantage of using these verbs is that you can avoid repeating the verbs fall and rise.
Verbs indicating a rise in in the value of something
Basic meaning: to rise in the air; to fly; rise beyond what is ordinary
Different forms: soars / soaring / soared
Soar can be used to describe large rises.
Prices of essential items have soared in recent times. (= There has been a large rise in the prices of essential items.)
Soaring prices make it difficult to make both ends meet.
Basic meaning: go up fast like a rocket
Different forms: rockets / rocketing / rocketed
Prices have rocketed.
Both soar and rocket can be used to talk about large rises. Note that the verb rocket describes a sudden, large rise. For example, when prices rocket, they rise dramatically over a short period of time.
Basic meaning: jump; sudden sharp rise
Different forms: leap / leaps / leapt / leaped
Basic meaning: go up; go higher
Different forms: climb; climbs; climbing; climbed
Climb is a relatively neutral word.
Verbs indicating a fall in the value of something
Plummet is perhaps the strongest of all verbs indicating a fall in the value of something. It can be used to indicate a sudden sharp fall.
Prices have plummeted.
Drop is used to describe fairly small decreases.
We have been witnessing a drop in prices over the last few months.
The temperature has dropped.
He dropped his voice to a whisper.
Dip, too, can be used to talk about fairly small fall in something.
Prices have dipped. (= There has been a small fall in prices.)
This verb can be used to talk about falls that come after rises.
Prices of apple and grapes rose in November, but slipped back again in December.