In this chart, price seems to keep testing the same value over days. Coincidence? Or science to explain it?

External question — Personal Finance Stack Exchange Author: trusktr Original post: https://money.stackexchange.com/questions/162997 License: CC BY-SA 4.0 — https://creativecommons.org/licenses/by-sa/4.0/ Adaptation: HTML converted to plain text; contact email addresses removed. Here's chart of the EUR/USD, and over the course of days, we can see that the current price seems to be tested by the low price on multiple previous days (the red line): Is this merely a coincidence? Or is there some science or theory that can explain this?

External answer — Personal Finance Stack Exchange Author: user3404 Original post: https://money.stackexchange.com/a/162998 License: CC BY-SA 4.0 — https://creativecommons.org/licenses/by-sa/4.0/ Adaptation: HTML converted to plain text; contact email addresses removed. Well if markets are rational you could just wave your hands and say that the consensus of the market in that period was that 1 British pound is worth around 1.274 USD, but with some slight differences in opinion, and very few people thinking it was less than 1.2685 or more than 1.281 USD, and that there was no news during that period to change that opinion in very many people. Really though if you pick any period, there are only 3 things that can happen: it can reach a minimum, reach a maximum, or it can fluctuate around an average. Calling it a fluctuation around an average doesn't sound like a call to action, so instead call it "testing the bottom of the market" or "testing the top of the market" depending on what you want people to do.