This is a fairly casual calculation of Beta; in reality, if you were measuring Betas, you'd want more data, but this gives you the intuitizin. It is standard to use three or five years of monthly data to calculate betas. You'll note that two securities with quite different standard deviations of returns have similar betas. Negative Betas?\ Q What kinds of investments might have a negative Beta?

This is a fairly casual calculation of Beta; in reality, if you were measuring Betas, you'd want more data, but this gives you the intuiticin. It is standard to use three or five years of monthly data to calculate betas. You'll note that two securities with quite different standard deviations of returns have similar betas. Negative Betas? Q What kinds of investments might have a negative Beta