The announcement of the Bank of Japan on stimulus measures affected the USD since the move was not enough to give the dollar a push forward.
The BOJ policy meeting on Friday said that it would widen the asset types that would be bought. This briefly increased the USD rate against the Yen.
But a turnaround happened when the USD slid after it was clear that the BOJ would not expand its money target base under the new stimulus program.
USD was 123.59 Yen just after the announcement but it went down by 0.5% at 121.895 Yen.
Ayako Sera, senior market economist at Sumitomo Mitsui Trust in Tokyo, said that the BOJ was fine tuning its policy which caused the decrease in the greenback value.
The Bank of Japan has decided to budget 300 Billion Yen in order to buy exchange traded funds or ETFs. The bank intends to get shares of companies that are dynamic in the pursuit of capital expenditure. The BOJ extended the maturity of JGBs from 10 years to 12 years starting 2016.
The greenback index is down by 0.4% at 98.910 after it hit a 99.294 overnight which the highest value is for a period of 2 weeks. The US dollar index had a 1.2% gain last Thursday. The USD rate increased widely after the Fed Reserve announcement on Wednesday of a lift on the benchmark rate from zero.