Looking to the past
Fried uses the early 1970s oil shock to calibrate her carbon tax model. The period of relative price stability leading up to the 1970s ended with a sudden and unexpected jump in oil prices, as shown below. Since then, there has not been a similar period of price stability, making the oil shock a unique historical example. Use the slider to zoom in and see the fluctuations in monthly oil prices over time. 
Source: Federal Reserve Bank of St. Louis