The graph shows the proportion of three vehicle registration in US in the period from 1970 to 2010.
Overall the registration for trunk vehicle was the highest percentage during the period, and the buses registration were the lowest number.
Trunk registration started at 48 percent, but then decreased sharply in the next ten years until it was 30 percent in 1980, that was the lowest value during its changes, and still in that proportion until 1990, but from then increased sigificantly which reached 45 percent in the year 2010.
The second place was Taxi registration, although it begins low at 22 percent, but then increased sharply which reached 35 percent in the year 1980,from then fall down until it became 15 percent in the year 2000, but then jumped to 35 percent.
The lowest curve was bus registration, which was 5 percent in the beginning. Athough it rised in 1980 which accounted 14 percent, but from that time started to decreased through all the period until it was 3 percent in the end.
