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$MD_{r,s}=MBASE_{r,s}*(1+({\frac {PRI_{r,s,t-1}*EXRATE_{r}-MPRIC_{r,s}}{MPRIC_{r,s}}}*\mathbf {elastrpr} _{s}))^{elmpr1}*(1+({\frac {PRI_{r,s,t-1}*EXRATE_{r}-MPRIC_{r,s}}{MPRIC_{r,s}}}-{\frac {PRI_{r,s,t-2}*EXRATE_{r,t-1}-MPRIC_{r,s,t-1}}{MPRIC_{r,s,t-1}}}*\mathbf {elastrpr} _{s}))^{elmpr2}$

${\frac {2}{3}}$

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