How long a bubble lasts depends on its impact on demand. The most lasting are property and technology bubbles. The multiplier effect of a property bubble is multifaceted. It stimulates both investment and consumption in the short term. The supply chain that it impacts is very long. From commodity producers to real estate agencies it could stimulate over one fifth of an economy on the supply side. On the demand side it stimulates credit growth and financial sector earnings, and often boosts consumption through the wealth effect. Because the property bubble is so powerful, the negative effect from its bursting is very damaging, because the excess supply during the bubble takes time to consume, and it destroys the credit system.
A technology bubble happens when investors exaggerate its impact on corporate earnings. A breakthrough technology like the internet improves productivity enormously. However, most of its benefit goes to consumers. Competition eventually shifts temporary high corporate profitability to lower consumer prices. Because the emergence of an important technology brings down consumer price, central banks often release too much money that travels into asset markets and create bubbles. As the underlying technology leads to an economic boom, the bubble feels real. More and more capital pours into the technology. It leads to overcapacity and destruction of profitability. The bubble bursts, when speculators finally realize that the corporate earnings wouldn’t come. The cost of a technology bubble is essentially the overinvestment. Because a breakthrough technology expands the economic pie, it makes it easier to absorb the cost of a technology bubble. Economy can recover relatively quickly.
Restocking by China’s state commodity reserve bureau played a large part in the record import volumes, as did easy credit from state banks, which encouraged some firms to buy commodities speculatively, according to the report.
Some producers took advantage of arbitrage opportunities presented by plummeting global commodity and shipping prices to replace domestic production with imported supply, illustrated by the steep drop in energy use in the first half of the year as energy-intensive miners and smelters shut down operations in favour of cheaper imports. Imports of unwrought copper and aluminium in the first half of the year were more than six times the level seen in 2006, when GDP growth was averaging 11 per cent, while monthly imports of crude oil and iron ore reached their highest ever level in July.