Volatility
Volatility measures how sharply an asset's price swings around its trend, and is usually expressed as the annualised standard deviation of its returns. It is the most widely used risk measure, though it has a known flaw: it treats sharp rises exactly like falls, and only the latter keep investors awake.
See also
See it on real data
Celsmar computes this from the accounts companies file with their regulator, and shows which line every figure comes from. Free to start, no card.
Definition for informational purposes. It is not financial advice nor a recommendation to buy or sell.