算出来为啥不除以total return，不是contribution么如何判断该不该除以

NO.PZ2018113001000083 问题如下 Bevis is aiser to WT, a funanagement firm. WT's clients are all high-net-worth clients in the U.S. Bevis manages the account for Clare, one ofhis clients, whiha totreturn of 4.418% last year. Bevis wants to calculatethe return e to the foreign currencontribution.Exhibit 1 summarizes the investmentinformation for Clare's account last yeCalculate the contribution of foreign currento the totreturn. Answer:the Clare account’s tot(US llar) return of 4.418%.The weighteasset return is equto 1.8%, calculatefollows:(60%×5%）+[ 40%×（-3%）] = 1.8%The mestic-currenreturn is equto the sum of the weighteasset return, the weightecurrenreturn, anthe weightecross-proof the asset return anthe currenreturn. The latter two terms explain the effects of foreign-currenmovements.Therefore, the contribution of foreign currenequals 2.618% = 4.418% - 1.8% .中文解析本题考察的是外汇投资中return的计算。要求解的“the contribution of foreign currency”是包含了两部分的，一是RFX，二是交叉项RFC ×RFX。因此，在总的return中减掉RFC 后，剩下的return就是由foreign currency贡献的return了。另外一种计算方法the contribution of foreign curren= wiRFX+wiRFCRFX=0.6*0.02+0.4*0.035+0.6*0.05*0.02+0.4*0.035*(-0.03)=2.618% 为什么asset return对应的是FX的变动？或者为什么这部分叫做asset return啊？不是汇率的变化吗？

NO.PZ2018113001000083 问题如下 Bevis is aiser to WT, a funanagement firm. WT's clients are all high-net-worth clients in the U.S. Bevis manages the account for Clare, one ofhis clients, whiha totreturn of 4.418% last year. Bevis wants to calculatethe return e to the foreign currencontribution.Exhibit 1 summarizes the investmentinformation for Clare's account last yeCalculate the contribution of foreign currento the totreturn. Answer:the Clare account’s tot(US llar) return of 4.418%.The weighteasset return is equto 1.8%, calculatefollows:(60%×5%）+[ 40%×（-3%）] = 1.8%The mestic-currenreturn is equto the sum of the weighteasset return, the weightecurrenreturn, anthe weightecross-proof the asset return anthe currenreturn. The latter two terms explain the effects of foreign-currenmovements.Therefore, the contribution of foreign currenequals 2.618% = 4.418% - 1.8% .中文解析本题考察的是外汇投资中return的计算。要求解的“the contribution of foreign currency”是包含了两部分的，一是RFX，二是交叉项RFC ×RFX。因此，在总的return中减掉RFC 后，剩下的return就是由foreign currency贡献的return了。另外一种计算方法the contribution of foreign curren= wiRFX+wiRFCRFX=0.6*0.02+0.4*0.035+0.6*0.05*0.02+0.4*0.035*(-0.03)=2.618% 请问4.418% 怎么算出来的

NO.PZ2018113001000083问题如下 Bevis is aiser to WT, a funanagement firm. WT's clients are all high-net-worth clients in the U.S. Bevis manages the account for Clare, one ofhis clients, whiha totreturn of 4.418% last year. Bevis wants to calculatethe return e to the foreign currencontribution.Exhibit 1 summarizes the investmentinformation for Clare's account last yeCalculate the contribution of foreign currento the totreturn. Answer:the Clare account’s tot(US llar) return of 4.418%.The weighteasset return is equto 1.8%, calculatefollows:(60%×5%）+[ 40%×（-3%）] = 1.8%The mestic-currenreturn is equto the sum of the weighteasset return, the weightecurrenreturn, anthe weightecross-proof the asset return anthe currenreturn. The latter two terms explain the effects of foreign-currenmovements.Therefore, the contribution of foreign currenequals 2.618% = 4.418% - 1.8% .中文解析本题考察的是外汇投资中return的计算。要求解的“the contribution of foreign currency”是包含了两部分的，一是RFX，二是交叉项RFC ×RFX。因此，在总的return中减掉RFC 后，剩下的return就是由foreign currency贡献的return了。另外一种计算方法the contribution of foreign curren= wiRFX+wiRFCRFX=0.6*0.02+0.4*0.035+0.6*0.05*0.02+0.4*0.035*(-0.03)=2.618% 交叉项里既有外国资产收益的贡献，也有外汇涨跌的贡献，为何计算时全都归入外汇贡献呢？

NO.PZ2018113001000083 问题如下 Bevis is aiser to WT, a funanagement firm. WT's clients are all high-net-worth clients in the U.S. Bevis manages the account for Clare, one ofhis clients, whiha totreturn of 4.418% last year. Bevis wants to calculatethe return e to the foreign currencontribution.Exhibit 1 summarizes the investmentinformation for Clare's account last yeCalculate the contribution of foreign currento the totreturn. Answer:the Clare account’s tot(US llar) return of 4.418%.The weighteasset return is equto 1.8%, calculatefollows:(60%×5%）+[ 40%×（-3%）] = 1.8%The mestic-currenreturn is equto the sum of the weighteasset return, the weightecurrenreturn, anthe weightecross-proof the asset return anthe currenreturn. The latter two terms explain the effects of foreign-currenmovements.Therefore, the contribution of foreign currenequals 2.618% = 4.418% - 1.8% .中文解析本题考察的是外汇投资中return的计算。要求解的“the contribution of foreign currency”是包含了两部分的，一是RFX，二是交叉项RFC ×RFX。因此，在总的return中减掉RFC 后，剩下的return就是由foreign currency贡献的return了。另外一种计算方法the contribution of foreign curren= wiRFX+wiRFCRFX=0.6*0.02+0.4*0.035+0.6*0.05*0.02+0.4*0.035*(-0.03)=2.618% （R+1）=（1+Rfc）*（1+Rfx），现在已经知道R和Rfc，直接用这个公式求Rfx=（R+1）/ （1+Rf- 1,为何不行？