For example, a discrete random variable X can take on a limited number of outcomes x₁, x₂, …, x_n (n possible outcomes), or a discrete random variable Y can take on an unlimited number of outcomes y₁, y₂, … (without end).1 Because we can count all the possible outcomes of X and Y (even if we go on forever in the case of Y), both X and Y satisfy the definition of a discrete random variable. By contrast, we cannot count the outcomes of a continuous random variable. We cannot describe the possible outcomes of a continuous random variable Z with a list z₁, z₂, … because the outcome (z₁ + z₂)/2, not in the list, would always be possible. Rate of return is an example of a continuous random variable.