China’s economic slowdown has dominated the news for months now, raising countless questions (and concerns). Since 1985, China's “socialist market economy" has seen otherworldly growth, surging from $200B to $10T GDP—a feat no other economy in history can claim.

But the methods that led to the unprecedented boom may have caused its equally epic collapse that could cause another US recession. Here are the four big bubbles that led to the Chinese crash, according to a report by Foreign Policy.

Exports

Exports make up 23% of China’s national income, but a large portion of exports' success comes from an artificially low exchange rate and subsidized credit from the government-controlled banking system, as well as significant foreign investment (which will only grow in the coming months). But, the world won’t take in as many exports as China is shipping out, especially considering that exports were growing at 20% annually and that credit-subsidized exporting firms in major cities (like Shanghai, shown) are reaching overcapacity.

Real Estate

Due to government policy, there's an oversupply of housing and commercial real estate in many major cities. In order to maintain growth and provide homes for a growing middle class, China’s government had to employ skilled and unskilled laborers to keep building, to the point where “ghost cities”—including Jingjin, which has thousands of unoccupied villas—now litter the landscape. There are also countless vacant offices, since province and city leaders built hundreds of office towers to attract companies that would employ citizens and pay taxes.

The fact that builders shared their profits with government officials who supplied permits, land and energy also made the boom unstable, and prices fell in major urban areas. (Not by much, however: new home prices only declined 3.7% between 2014 and 2015, and many of these spaces are out of reach for many Chinese citizens.)

Fortunately, even with the price falls and housing overstock, the residential housing bubble is mainly funded by private funds, so only private individuals felt the sting, while the mortgage industry remains unaffected and won’t collapse as it did in 2008. Office space, however, does depend on bank loans, and all the unoccupied space led to non-performing loans.

Infrastructure

After recessions in the early 2000s, the Chinese government started a public works program to maintain economic growth. However, the program and the facilities built--such as the Olympic facilities (shown)--are largely underutilized, leading to wasted capital that could've been spent better. For one, the country's toll roads wasted $25B last year. The fact that the programs’ billions come from state-affiliated banks, combined with the vicious cycle of local governments leasing land to private developers that then work with government officials, infrastructure continues to be a source of huge losses.

State-Owned Enterprises

The Chinese government has its hand in dozens of sectors (such as Air China in the travel sector), employing millions and making up 40% of China’s GDP. Unfortunately, the monopolies and oligopolies in each sector are inflexible to market conditions. In addition, many of the workers got jobs through political connections, so firing these people is pretty much impossible. Worse, these enterprises don’t compete in the global market and continue to rack up debt, eventually requiring a bailout.

The Chinese government has to deflate all of these bubbles if it's to have a more stable economy, but doing so without causing huge job losses or even greater capital loss seems almost impossible. [FP]