For the first time in four months, BofAML’s Global Financial Market Stress index has turned positive. The continuing growth signals that global central banks lose control and the market is stressed more than normal.

As tensions between North Korea and the US escalated, a measure of cross-asset risk, hedging demand and investor flows rose compared with the past 78 days, when the market stress had been below normal and had indicated a high level of calm among investors and traders. Now the situation is changing, however, it is not clear yet whether this is a result of growing global tensions or the logical conclusion of a tranquil period.

This is the biggest spike in the Global Financial Stress Index since August 2011 and even a bigger increase than that in August 2015 after devaluation of the Chinese yuan.

Markets continue to expand, so the fall could be even steeper. Potential war with North Korea and Venezuela, trade war with China, as well as social and political instability in the United States can have a serious impact on the US stock market.