Vocabulary to represent frequent changes in graphs:

 Vocabulary to represent frequent changes in graphs: 

Type of Change	Verb form	Noun form
Rapid ups and downs	wave / fluctuate / oscillate / vacillate / palpitate	waves / fluctuations / oscillations / vacillations /  palpitations

Example:  

1. The price of the raw materials fluctuated for the first three months.

2. The graph shows the oscillations of the price of fuel from 1998 to 2002.

Vocabulary to represent highest and lowest point in graphs: 

Type	Verb	Noun
Highest Point	peak / culminated / climax / reach  a peak / hit a peak / touch the highest point / reach the vertex	a peak / hit a vertex / get a vertex / get the highest point
Lowest Point	touched the lowest point / get the lowest point /	the lowest point /the lowest mark / bottommost point / rock bottom point/ bottommost mark

 Example: 

1. The price of the oil reached a peak amounting $20 in February and again touched the lowest point amounting only $10 in July.

2. Student enrollment in foreign Universities and Colleges increased dramatically hitting a peak of over 20 thousand in 2004.