Japanese basic wages adjusted for inflation dropped to 98.9 on a Labor Ministry index in 2013, matching the level of 2009.
The fall stands in contrast to the government's efforts to encourage companies to increase salaries in order to strengthen the Bank of Japan's battle against deflation.
The data came as business and union leaders started this year's salary negotiations. "Each company will do their utmost to increase wages depending on their earning situation," said Hiromasa Yonekura, the head of Keidanren, Japan's largest business lobby.
The USD-JPY is -0.35% at ¥101.29, while the Nikkei closed +1.2% after falling sharply over the past few sessions.