The line graph compares the usage rate of energy sources among households from before 1950 to 2010. 
 
Overall
, most buildings utilised natural gas to heat them throughout the given period, but the trend of its usage experienced a maintenance and a slight decline. Linking Words
On the other hand
, the percentage of electricity-driven Linking Words
system
 steadily increased during the same time. 
 In detail, before 1950, 60% of constructions were made with natural gas, and Fix the agreement mistake
systems
this
 movement remained until 1969. Linking Words
However
, the number of houses which were with it dropped to about 45 per cent, Linking Words
then
 Linking Words
also
 kept the identical ratio again up to 2010. Linking Words
Whereas
Linking Words
,
 the fraction of electrically heated houses went up step-by-step over the same era. Before 1950, it was a little above 0.1 of the total amount, before jumping to a quarter of the total, Punctuation problem
apply
then
 over 30%. Linking Words
Finally
, it matched with that of houses with gas energy at 45% between 1990 to 2010.Linking Words