Bulletin – September 2015 Equation (A3)

\begin{array}{l} E = A Φ [d_{1}] - L e^{- μ τ} Φ [d], \\ d_{1} = \frac{\ln [\frac{A}{L}] + (μ + \frac{σ_{A}^{2}}{2}) τ}{{σ^{'}}_{A} \sqrt{τ}}, \\ d_{2} = d_{1} - σ_{A} \sqrt{τ}, \\ σ_{A} = \frac{E σ_{E}}{A Φ (d_{1})} \end{array}