The use of fossil fuels, which has increased steadily since the beginning of the 20th century, has enabled many advancements in the quality of life around the world.  However, fossil fuels are a limited resource and could become scarce during the 21st century.  To create projections for future global energy consumption, we can apply lines of best-fit to historical data. There are several estimates of fossil fuel reserves remaining in the earth and these estimates are continually revised.  In order to estimate when fossil fuels will be exhausted, we can equate the total fossil fuel resource base with the integral of our line of best-fit and solve for the time. The data in this episode is taken from 2012 studies on fossil fuel consumption.