The proportion of vehicle registration

Question

The given line chart illustrates the percentage of three different types of commercial vehicles registered in America through a 4-decade period beginning from 1970. 
As can be observed from the provided chart, it is obvious that although the proportion of three modes of transportation changed over the period, trucks still made up the largest share, followed by taxis and buses. 
In 1970, the majority of registrations were trucks while the humble of 25% and 5% of vehicles being registered were taxis and buses, respectively. The rate of taxis and bus soared noticeably to the highest point before being witnessed a remarkable fall after that period until 2000 when the upward trend was only seen in the rate of taxi registration. 
By contrast, this figure for trucks dropped dramatically in 1980 to 30% which made it ranked in the second position. The rate started to rise gradually to more than 30% in 1990 and grew back to approximately 45% at the end of the period.