During risk-off times, the only two currencies to appreciate relative to the USD are the Yen and the Swiss franc. A study found that the best asset classes to hold in risk-off conditions are US Treasuries and the yen. read more
The second is the devaluation of the yen which took it down by about 39% in nominal terms relative to the dollar from 2011 to today. In the case of the pound, our PPP metric indicated that the pound was overvalued by about 20% in 2007, and then progressed to being undervalued by nearly 18%, for a 38% swing (chart 4). read more
The Yen is viewed as a "safe haven" currency, so it is usually in demand during times of economic stress. Looking at a 5 year chart, the Yen has appreciated significantly, so you could argue that it is overvalued but that does not mean that the Yen is due to depreciate. read more