Japanese workers’ wages have jumped by more than twice the pace expected by economists as annual pay hikes fed into monthly data, offering the Bank of Japan a sign that upward momentum in pay may be strengthening.

Nominal cash earnings for Japan’s workers rose 2.5% in May from the previous year, the labor ministry reported Friday. The results blew past analysts’ expectation of a 1.2% gain, and may maintain market speculation that the central bank will consider adjusting policy sooner rather than later.

The gains still left households worse off as pay failed to keep up with rising prices, a factor that will likely weigh on consumption. Real cash earnings fell 1.2% from a year earlier in May though decreasing less than economists forecast.