The meaning and definition of Standard Deviation -

The meaning and definition of Standard Deviation -
A statistical measure of the average volatility of a security's returns in relation to its average value. Money-market securities, which generally have stable asset values, have standard deviations of zero. More volatile, aggressive-growth portfolios usually have a higher percentage of deviation. Standard deviation gives the investor an idea of how much a security's price can be expected to fluctuate based on past norms.