The Yen's falling trend is a combination of 2 leading factors. The first one is an instable economic data which shows that the Japanese economy is yet to pull out of recession. The second one is the Bank of Japan, which keeps it as its main interest to weaken the Yen, in order to support the Japanese export. The Mixed results from the Japanese economy continued last week; one hand, the Trade Balance, which measures the difference in value between imported and exported goods and services rose to 0.49T during November, on the other hand, the Tokyo Core Consumer Price Index, a leading gauge for inflation, dropped by 1.9% during December. This shows that Japanese consumers did not regain their confidence regarding their financial security, and thus prefer to avoid expenses at the moment.
As for this week, not many economic publications are expected from Japan, as Japanese banks won't work during most of the week. Traders are advised to follow the leading publications from the U.S. economy and Euro-Zone, as they are likely to impact the Yen this week.