The thing to keep in mind re: oil in particular is that a stable oil price is indicative of increases in supply to match the more or less continuous increase in

The thing to keep in mind re: oil in particular is that a stable oil price is indicative of increases in supply to match the more or less continuous increase in demand over most of that period. The big dislocations you cite obscure the fact that demand rose for most of the period, demand was rising. So another way to read the chart is that demand-weighted prices declined most of the time, with occasional spikes. Either way, you can see in the charts the increased supply effect of e.g. fracking being deployed widely in the price response. One could also look back to 2008 to see the impact of increased supply on pricing of e.g. real estate.