Shares of US retail giant Wal-Mart Stores plunged nearly nine percent as the company cut its near-term profit and sales outlook due to heavy employee wage and store investment.

Wal-Mart trimmed its current fiscal 2016 sales outlook to "relatively flat" from a prior projection for a gain of one-two percent, citing the strong dollar. It said earnings per share will fall between six and 12 percent in fiscal 2017, which will be its "heaviest" period of investment.