Yield-starved Japanese investors are taking out the cash stashed under the futon and plowing it into potentially risky securities.

Faced with domestic bond yields below zero and a rally in global equities that only recently had some wobbles, domestic retail investors drove sales of bonds tied to the Nikkei 225 stock average to the highest in at least three years in January, according to Societe Generale SA.

This marks a comeback for the so-called uridashi notes, offerings of which tumbled 24 percent back in mid-2015, when weak energy prices and worries about China triggered a risk-off mood in markets. The securities pay off if the stock index rises above a preset level on designated days. The Nikkei 225 stock average climbed to 17-year highs in dollar terms after U.S. President Donald Trump's election, prompting early redemption of the notes linked to the gauge and a rollover of the money into new offerings for Japanese investors.