The two pie charts illustrate 
proportion
 of electricity gained by various Add an article
the proportion
energy
 sources in Scotland Use synonyms
for 
twenty years ago and Change preposition
apply
for 
Change preposition
apply
last
 year.
Linking Words
Overwhelming
 majority of Add an article
The overwhelming
An overwhelming
energy
 Use synonyms
generated
 by coal regardless of periods of time.
There is a notable increase in Add a missing verb
is generated
demands
 Fix the agreement mistake
demand
of
 nuclear Change preposition
for
as 
Change preposition
apply
a 
Correct article usage
apply
energy
 Use synonyms
source
 from 19.6 Use synonyms
Use synonyms
percent
 to 26.4 Change the spelling
per cent
Use synonyms
percent
. Change the spelling
per cent
Conversely
, the most declined Linking Words
source
 is Use synonyms
a coal
 went from 41.4 Remove the article
coal
a lump of coal
Use synonyms
percent
 to 32.7 Change the spelling
per cent
Use synonyms
percent
. Change the spelling
per cent
Gas
 kept stability in Add an article
The gas
energy
 Use synonyms
producing
 with Replace the word
production
tiny
 Correct article usage
a tiny
descend
 from 22.3 Replace the word
descent
Use synonyms
percent
 to Change the spelling
per cent
an 
21.7 Correct article usage
apply
Use synonyms
percent
. Hydro natural flow as an Change the spelling
per cent
energy
 Use synonyms
source
 Use synonyms
used
 decently with having Add a missing verb
was used
proportion
 of 8.7 Add an article
a proportion
the proportion
Use synonyms
percent
 and Change the spelling
per cent
last
 year lowered it to 7.9 Linking Words
Use synonyms
percent
. Oil with 2.1 Change the spelling
per cent
Use synonyms
percent
 being Change the spelling
per cent
most
 unpopular Correct article usage
the most
source
 increased in demand to 4 Use synonyms
Use synonyms
percent
, leaving behind Change the spelling
per cent
hydro pumped
 storage Add a hyphen
hydro-pumped
with
 2.2 Change preposition
at
Use synonyms
percent
.Change the spelling
per cent