The pie charts give information about the division facts of 
school
 costs in five categories Use synonyms
the
 United Kingdom in two decades in the years 1981 to 2001. 
Change preposition
in the
Overall
 , it can be clearly seen that over the whole period of Linking Words
20years
 was the most significant Correct your spelling
20 years
school
 expenditure Use synonyms
to
 the Change preposition
on
teachers
 salaries . Change to a genitive case
teacher's
teachers'
While
Linking Words
,
 the least significant Remove the comma
apply
school
 spending to Use synonyms
the 
insurance. Correct article usage
apply
Also
 , Linking Words
that 
it clearly shows that the resources and furniture have a levelling off at one decent. Correct word choice
apply
Furthermore
 , Linking Words
others
 employees were highest in all periods.
Correct quantifier usage
other
1981
 , Change preposition
In 1981
teachers
 salaries experienced a significant increase reached by 40% . Change noun form
teachers'
teacher's
Follows next
 spending by Verb problem
Next
others
 Correct quantifier usage
other
workers
 fees accounted for 28% . Interestingly, resources Change noun form
workers'
worker's
for example
 , books and furniture  Linking Words
for instance
, equipment remained the same Linking Words
school
 expenditure accounted for 15% percentage . 
Total spending Use synonyms
school
 wages for workers in 1991 , instructors wages respectively was the highest in 2 decades in 1991 accounts for 50% . Use synonyms
Whereas
 , Linking Words
others
 employees were decreased rate 22%. Resources like books Correct quantifier usage
other
was
 increased by 20% . Furniture like equipment , Change the verb form
were
was 
sharply Unnecessary verb
apply
go
 down Wrong verb form
went
reached to
 5 % .Wrong verb form
reaching