Editing Business cycle (section)

=== Upper turning points of business cycle, commodity prices and freight rates ===
There is often a close timing relationship between the upper turning points of the business cycle, commodity prices, and freight rates, which is shown to be particularly tight in the grand peak years of 1873, 1889, 1900 and 1912.<ref>Jan Tore Klovland {{cite web |url=http://econpapers.repec.org/article/eeeexehis/v_3a46_3ay_3a2009_3ai_3a2_3ap_3a266-284.htm |title=EconPapers: New evidence on the fluctuations in ocean freight rates in the 1850s |access-date=2013-07-30 |url-status=live |archive-url=https://web.archive.org/web/20140222133500/http://econpapers.repec.org/article/eeeexehis/v_3a46_3ay_3a2009_3ai_3a2_3ap_3a266-284.htm |archive-date=2014-02-22 }}</ref> Hamilton expressed that in the post war era, a majority of recessions are connected to an increase in oil price.<ref>Hamilton, J. D. (2008). Oil and the macroeconomy, in S. N. Durlauf & L. E. Blume, eds, "The New Palgrave Dictionary of Economics".</ref>

Commodity price shocks are considered to be a significant driving force of the US business cycle.<ref>Gubler, M., & Hertweck, M.S. (2013). (p. 3-6). "Commodity Price Shocks and the Business Cycle: Structural Evidence for the U.S".</ref>

Along these lines, the research in [Trimbur, 2010, ''International Journal of Forecasting''] shows empirical results for the relation between oil-prices and real GDP. The methodology uses a statistical model that incorporate level shifts in the price of crude oil; hence the approach describes the possibility of oil price shocks and forecasts the likelihood of such events.<ref>{{cite journal |last1=Trimbur|first1= Thomas M. |year=2010 |title=Stochastic outliers and levels in time series with application to oil prices| journal=International Journal of Forecasting}}</ref>