Exchange-rate equilibrium calculations from the 1970’s and 1980’s, which could only have been based on the export sector’s contemporary structure, naturally would have little relevance subsequently. The same is true of calculations at the beginning of the 1990’s, which would have forecast Japanese import growth based on extrapolations from the high GDP growth rates of the previous 40 years rather than on the decade of stagnation that ensued.
对从二十世纪七十年代到八十年代的汇率平衡的计算只能基于出口产业当时的结构来进行，自然对以后的状况在很大程度上就缺少了关联性。同样的情况也出现在对二十世纪九十年代初期汇率平衡的计算上，它根据前面40年很高的GDP增长率而不是后面即将出现的十年的停滞期来预测日本的出口增长。