It is the largest decline since October and far below expectations which was a decline of 0.3 percent, according to Bloomberg's forecast.
During the first five months of the year, the total decline is 1.1 percent compared to the same period last year.
The winning streak signals weaknesses in an economy that is being squeezed by the US's tightened tariffs and a persistent deflationary pressure.
The deterioration can make companies more reluctant to invest and hire. It also highlights the need for more government stimuli.
