円高・円安に基準ってあるの？について調べてみた。

　I have my doubts about what is the standard(basis) for deciding whether
Japanese yen is stronger compared to CAD.
　In conclusion, there are no deinite standard. It depends on the stand on individual or observaiotn period.
　For example, A traveled America 3 years ago when 1 dollar is same as 120 yen. Now 1 dollar is same as 87 yen. So,she can think that Japanese yen is stronger. On the other hand, B bought foreign currency 3 months ago when 1 dollar is same as 80 yen.Now 1 dollar is same as 87 yen, so he can think that Japanese yen is weaker.
　Period of seeing exchange rate leads to make a big defference to them.

　In general,thinking based on economic, there is likely to be standard about average of 3 months exchange rate. That's why critical econimic index every 3 months.
　[Therefore]=従って,  when 1 dollar was equal to 90 yen for last 3 months and 1 dollar is equall to 80 yen, Japanese yen is stronger than U.S dollar.
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　There is an interesting index to mearsure exchange rate. It is big mac index. It make use of price of big mac decided based on many 【factor(elements)】=要素 such as cost of land and 【ingredient】(料理の材料)material＝DIY,資料など .
　Lower big mac index means that prices is low. Compared to U.S, Chainese prices is much lower than U.S. because big mac index is minus
45%.