At a rate of 9.61 kronor to the dollar, the krona has fallen 4.15 percent so far this year, according to the Bloomberg news agency's weekly dollar index.
It is the worst performer of the so-called G10 currencies - the most traded and liquid currencies in the world.
Other G10 currencies that have lost ground against the US dollar are the Japanese yen, down 2.11 percent, and the Swiss franc, down 2.04 percent.
The Norwegian krone has been the strongest performer, up 7.61 percent against the dollar. The Australian and New Zealand dollars have risen 7.36 and 2.73 percent respectively.
Last year, it was instead the Swedish krona that strengthened against the US dollar week after week.
