Skip to content
All library documents

Why a Chinese Yuan Devaluation Can Shift EUR/USD Expectations

Article Quant Q&A · Author: emcor
Read the original

Summary

The document asks why the euro strengthened against the US dollar after an unexpected devaluation of the Chinese yuan, despite expectations that US rate increases would favor the dollar. The response offers a possible link: market participants may have revised expectations for Federal Reserve tightening after the currency move, weakening the dollar. A contemporaneous financial headline is cited as evidence that the expected timing of a rate increase was being reconsidered.

The answer treats this as a plausible interpretation rather than a proven causal account. It emphasizes that market reactions are difficult to explain in real time and that, after prices move, several narratives may seem to fit. The discussion does not compare competing hypotheses or establish that the yuan move alone caused the exchange-rate change. Its practical lesson is to distinguish observable price moves and policy expectations from confident stories about why markets moved.

Key ideas

  • A currency devaluation can affect exchange rates indirectly by changing expectations for central bank policy.
  • The response links dollar weakness to the possibility that markets postponed expected Federal Reserve tightening.
  • A contemporaneous news headline is offered as support for that interpretation.
  • Post hoc explanations can sound plausible without being independently verified.
  • The exchange does not establish a definitive causal relationship between the yuan move and EUR/USD.

Tags

ForexChina marketsUS marketsEvent-driven
Full text
# CNY Devaluation: Why EUR up, USD down?


# CNY Devaluation: Why EUR up, USD down?












The second unexpected devaluation of the Chinese currency CNY caused some turbulent market movements in currencies today.

I was surprised that the EUR went to a 1-week high against the USD up by almost 1.5% on a single day to a 1-month high.

Can someone explain why the CNY devalutation would benefit the EUR and harm the USD?

As we know, the EUR offers a negative ECB rate, while the fed is expected to raise its rate, hence I expected the USD to rise vs. the EUR. Then I thought that maybe together with a solution of the Greek debt crisis markets preferred going into EUR and saw the USD already overvalued.

## Answer by nbbo2 (score 6, accepted)

https://quant.stackexchange.com/a/19303

Today (1 day after the fact) the following headline appeared in the Financial Times: "September Fed rate lift-off put in doubt, Fallout from China’s currency move turns market mood". If true, this would certainly explain why the USD declined (i.e. the interest rate rise that everyone expected has been postponed). However, in my experience it is very hard to understand these things as they happen or before they happen. After the fact, once you know what happened, many explanations look plausible, but they are impossible to check against each other. The public wants an explanation. but the markets are complex and not easy to decipher.

Shown in full with attribution under the source's licence. Licence: CC BY-SA 4.0 (Stack Exchange)

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.