Japanese consumers and workers with jobs sensitive to economic trends regained confidence in May, signalling optimism that the impact of the first sales tax hike in 17 years will wane soon, government surveys said Monday.

The seasonally adjusted index of sentiment in households of two or more people rose 2.3 points from a month earlier to 39.3 in May, the first gain in six months, the Cabinet Office said. Readings below 50 suggest pessimists outnumber optimists.

The basic assessment was upgraded of the index for the first time in eight months, saying sentiment "has shown signs of picking up."