not because he believed it to be literally correct. The study observed that in most cases the asymmetric exponential model provided a better fit (as in the case of Seneca cliff model), and that peaks tended to occur well before half the oil had been produced, with the result that in nearly all cases, the post-peak decline was more gradual than the increase leading up to the peak. Demand The demand side of peak oil over time is concerned with the total quantity of oil that the global market would choose to consume at any given market price. The hypothesis that peak oil would be driven by a reduction in the availability of easily extractable oil implies that prices will increase over time to match demand with a declining supply. By contrast, developments since 2010 have given rise to the idea of demand-driven peak oil. The central idea is that, in response to technological developments and pressure to reduce carbon dioxide emissions, demand for oil at any given price will decline. In this context, the development of electric vehicles creates the possibility that the primary use of oil, transportation, will diminish in importance over time. After growing steadily until around 2006, oil demand has fluctuated, falling during recession periods, and then recovering, but at slower growth rates than in the past. Oil demand fell sharply during the early stages of the COVID-19 pandemic, with global demand for oil dropping from 100 million barrels a day in 2019 to 90 million in 2020. The drop in demand is not expected to recover until at least 2022, and British Petroleum predicts that oil demand will never recover to pre-pandemic levels due to increased proliferation of electric vehicles and stronger action on climate change. Developments in 2021 at Exxon, Chevron and Shell also lent further credence to the idea that peak oil had happened in 2019. Energy demand is distributed amongst four broad sectors: transportation, residential, commercial, and industrial. In terms of oil use, transportation is the largest sector and the one that has seen the largest growth in demand in recent decades. This growth has largely come from new demand for personal-use vehicles powered by internal combustion engines. This sector also has the highest consumption rates, accounting for approximately 71% of the oil used in the United States in 2013. and 55% of oil use worldwide as documented in the Hirsch report.