Stock returns
In academic literature, it is more common to base analysis on stock returns and log returns of the close price. Simple returns are just the rate of change from one value to the next. Logarithmic returns, or log returns, are determined by taking the log of all the prices and calculating the differences between them. In high school, we learned that:
Log returns, therefore, also measure the rate of change. Returns are dimensionless, since, in the act of dividing, we divide dollar by dollar (or some other currency). Anyway, investors are most likely to be interested in the variance or standard deviation of the returns, as this represents risk.
