The 2008 housing bust suggests China's only halfway through its property crisis. Here's how the downturns compare.

• The 2008 US housing bust suggests China is only halfway through its current downturn, Goldman Sachs said.
• China could see further declines in prices, housing starts, and new home sales, the bank said.
• The 2008 crisis differs from China's, but policymakers must similarly work to prevent contagion.

The 2008 US housing market crash stands as one of the worst collapses in economic history — and its lessons remain relevant as China deals with its own real estate crisis.