Elsewhere, there are problems too, because Africa and much of Latin America depend on commodity exports, and Russia on energy.
Many emerging markets depend on commodity exports, and growth and prosperity in the emerging economies also drive trade amongst them.
Mongolia's mining boom depends on commodities demand from China, whose economy has slowed this year.
With growing demands for sustainably produced agricultural produce for environmental, social and food safety reasons, the use and recycling of organic matter is becoming inevitable, particularly for the export market, which depended on commodities such as coffee.
And they depend on one commodity that is not immediately evident from the current state of Holyrood-Westminster relations: a mutual desire for co-operation and stability.
Many sub-Saharan countries depend on one commodity, such as oil or gold, so country currencies can go up and down with the value of that commodity, which can damage the underlying economies.
Yet most of the estimated $50 billion that might have been saved on direct payments over 10 years — and perhaps far more, depending on commodity prices — was plowed back into other subsidy programs.
It depends on commodity prices, technology, the cost of transport, and any number of other dynamic variables.
In addition, assumptions about how demand for different commodities depends on commodity price (the so-called elasticity factors) are of great importance and vary significantly among the models.
Additional income has come from taxes on local businesses, many of which also depend on cheap commodities from the tunnels that are now in short supply.
