Finance School of management Contribution of security i to the Market risk E(rM)=∑xME(r1) M ∑xM/oiM LE()-rfI E()=r+ M uesTc11 Finance School of Management Contribution of Security i to the Market Risk =  i M i M i E(r ) x E(r ) =  i s M xiMs iM 2 i M M M f i f E r r E r r s s [ ( ) ] ( ) − = +