The bar chart given illustrates the percent of hight-weawed speaking themes, which were used from 2015 to 2017.
Overall, the most used topics in each years were about Events and it ammounted approximately more than 45%, while topics such as about people, object and plece were ammounted under 20%.
In below years themes for speaking about people were 14-16%, while topics about were used 12-14. But topics about object were used from between 10-14%. All of these themes were used under 20%, but up 10 percents.
According to the chart, the most used topic was event, which in 2015 had a rate of about 49%. It was the highest rate. In 2016 it 45%, which was the lowed rate. In 2017 it was used in 48%. topics such as about media, society and others were used under 10% in each of given years.
