As the bubble emerges, there are fewer productive investments, and at the same time there is more capital going after them. The fundamental attractiveness of the country that sparked the boom fades, in part because the rising currency is eroding the country’s competitiveness.

During this stage, growth is increasingly financed by debt rather than productivity gains, and the country typically becomes highly reliant on foreign financing. This shows up in foreign currency denominated debt rising. These emerging countries typically borrow primarily from abroad with debts denominated in foreign currencies because of a combination of factors—including the local financial system not being well developed, less faith in lending in the local currency, and a smaller stock of domestic savings available to be lent out.

这里讲的情况其实挺像当年东南亚四小龙、四小虎的情况的，美元最后1997年收割一波20年的经济成果。

Below we summarize the conditions through the upswings that led to the 27 inflationary deleveragings we looked at. We break out the cases with higher and lower levels of foreign-denominated debt and the cases that eventually had the least and most extreme economic outcomes (as measured by most severe declines in growth and equity prices and increases in unemployment and inflation). As you will see, the countries that were most externally reliant through the upswing and experienced the biggest asset bubbles ultimately experienced the most painful outcomes.

这儿总结了几个技术性的指标，针对通胀型去杠杆（一般是发展中国家），可以看到外债一本都是很多的，外汇储备一般也有GDP的10%，资本流入占GDP的10~20%。

In the typical cycle, the crisis arises because the unsustainable pace of capital that drove the bubble slows, but in many cases, there is some sort of a shock (like a decline in oil prices for an oil producer). Generally the causes of the top-reversal fall into a few categories: 1) The income from selling goods and services to foreigners drops (e.g., the currency has risen to a point where it’s made the country’s exports expensive; commodity-exporting countries may suffer from a fall in commodity prices). 2) The costs of items bought from abroad or the cost of borrowing rises. 3) Declines in capital flows coming into the country (e.g., foreign investors reduce their net lending or net investment into the country). This occurs because: a) The unsustainable pace naturally slows, b) Something leads to greater worries about economic or political conditions, or c) A tightening of monetary policy in the local currency and/or in the currency those debts are denominated in (or in some cases, tightening abroad creates pressure for foreign capital to pull out of the country). 4) A country’s own citizens or companies want to get their money out of their country/currency. Weakening capital flows are often the first shoe to drop in a balance of payments crisis. They directly cause growth to weaken because the investment and consumption they had been financing is reduced. This makes domestic borrowers seem less creditworthy, which makes foreigners less willing to lend and provide capital. So, the weakening is self-reinforcing. •• Growth slows relative to potential as the pace of capital inflows slows. •• Domestic capital outflows pick up a bit. •• Export earnings fall, due to falling prices or falling quantities sold. Typically exports are flat, no longer rising.

当泡沫即将破裂会有集中信号：

  1. 出口减少（因为货币的升值导致价格竞争力下降）
  2. 进口成本变高或者借外债成本变高
  3. 外国资本因多种原因流入的速度变慢，甚至流出（比如美元利息变好）
  4. 国民信心下降导致想把资产转移