The pie chart gives data related to 
proportion
 of volunteers based on organization types in 2008 and 2014.
Add an article
the proportion
Overall
, some categories Linking Words
such
 as Linking Words
Enviromental
 and Art Correct your spelling
environmental
were 
declined over the period Unnecessary verb
apply
while
 Linking Words
Enviromental
 and Others categories Correct your spelling
environmental
indicates
 an Change the verb form
indicate
increased
.
Replace the word
increase
According to
 the data, Educational Linking Words
was
 the highest percentage of volunteers by group with 24% in 2008. Six years later, the proportion of it showed a drop from 24% to 17%. Verb problem
had
Similarly
, the data for Art members Linking Words
also
 Linking Words
had shown
 a decline Wrong verb form
showed
by
 6%. Change preposition
of
In contrast
, environmental Linking Words
activist
 shared an increase in the percentage from 21% in 2008 to 29% in 2014.
 In 2014, Health Care displayed a Fix the agreement mistake
activists
slightly
 increase at around 8% which is 1% higher than Change the adverb
slight
percentage
 in 2008. Add an article
the percentage
Futhermore
, a significant Correct your spelling
Furthermore
rose
 Replace the word
rise
Linking Words
also
 witnessed in Add a missing verb
was also
sport team
 that involved 10% in 2014 compared to 15% involvement in 2008. Fix the agreement mistake
sports teams
Dispite
 Correct your spelling
Despite
of 
these Change preposition
apply
increase
, Fix the agreement mistake
increases
Others
 category showed a drop from 15% to 9% in 2014.Correct article usage
the Others