The line graph shows the change in oil prices from 1973 to January 2009.
Overall, oil prices increased during this period, but they fluctuated a lot. Although prices went from $10 to $140 with continuous ups and downs, it varied greatly during certain periods and remained stable in the others.
In the 1970s, prices rose sharply, reaching $40. However, during 1980 and 1990, prices generally fell and remained low, varying between $15 and $30. From 2000, prices had a steady increase and reached the all-time high, more than $140. Later, it was steeply reduced back to around $40 by January 2009.
In summary, this graph gives the historical oil price variation over more than three decades. The oil prices increased and decreased continuously on a minor scale until the sudden increase, which came in 2006. This dramatic rise and fall of the oil price is shown in the graph.