The given chart compares the proportion of six kinds of resources contributing to generate the power in three separate years, namely 1970, 1980, and 1990.
Overall, as can be seen in the pie chart, hydro is the most utilized resources in 1970 and 1980. Geothermal was the second largest resource being used in 1970 and became the biggest percentage in the year 1990. Furthermore, it was not until 1980 than the nuclear power was taken advantage of.
Turning into detail, it is salient that the dominant resource is the hydro in both 1970 and 1980, accounting for 45% and 76%, respectively. By the same token, the geothermal resource was the second place in 1970 and 1980, comprising nearly a quarter in 1970, and declining to below 10% in 1980. Nevertheless, by the year 1990, it is interesting to note that “lion shares” was attributed to the geothermal, making up approximately 40% of the whole. Meanwhile, the hydro resource fell into the second place, taking up about one three.
The most striking point is that there had been no utilization of nuclear before 1980. However, the nuclear was the third largest source of power by the year 1990, constituting roughly a quarter of the entire resource. 
The  
given
 chart compares the proportion of six kinds of resources contributing to generate the power in three separate years,  
namely
 1970, 1980, and 1990. 
Overall
, as can be  
seen
 in the pie chart, hydro is the most utilized resources in 1970 and 1980. Geothermal was the second largest  
resource
 being  
used
 in 1970 and became the biggest percentage in the  
year
 1990.  
Furthermore
, it was not until 1980 than the nuclear power  
was taken
 advantage of.
Turning into detail, it is salient that the dominant  
resource
 is the hydro in both 1970 and 1980, accounting for 45% and 76%,  
respectively
. By the same token, the geothermal  
resource
 was the second place in 1970 and 1980, comprising  
nearly
 a quarter in 1970, and declining to below 10% in 1980.  
Nevertheless
, by the  
year
 1990, it is interesting to note that “lion shares”  
was attributed
 to the geothermal, making up approximately 40% of the whole. Meanwhile, the hydro  
resource
 fell into the second place, taking up about one three.
The most striking point is that there had been no utilization of nuclear  
before
 1980.  
However
, the nuclear was the third largest source of power by the  
year
 1990, constituting roughly a quarter of the entire  
resource
.