The Treynor measure (or Treynor ratio) evaluates the excess return of a portfolio per unit of systematic risk (measured by Beta). The formula is: $Treynor\ Ratio = \frac{E(R_p) - R_f}{\beta_p}$ Given:

• Expected Return of Portfolio M, $E(R_p)$ = 8% = 0.08
• Risk-free rate, $R_f$ = 4% = 0.04
• Beta, $\beta_p$ = 0.8

Calculation: $Treynor\ Ratio = \frac{0.08 - 0.04}{0.8} = \frac{0.04}{0.8} = 0.05$ Therefore, the Treynor measure is 0.05.