Trading range
How far did a market travel between its weekly low and high, and why is that different from the weekly return?
In plain words
The trading range is the distance between the lowest and highest prices in a period, expressed as a percentage of the low. The weekly return is simply the change from the opening price to the closing price, so it can be small even when the range is very wide.
Why it matters
The return shows where the week ended; the range shows how much risk was endured along the way. A narrow return can conceal a violent path that would have stopped out leveraged positions or triggered liquidations long before the close.
In a real week: ETH, week of 16 March 2020
In the week of 16 March 2020, ETH ranged 50.89% from its low of 101.10 on Monday at 10:00 UTC to its high of 152.55 on Friday at 10:00 UTC, yet the weekly return was only -1.21%, with an open of 123.82 and a close of 122.32. The week travelled far and finished almost where it began.
A common mistake
Judging a week by its return alone. A near-zero return can hide a range wide enough to destroy any position sized for a quiet week.