Nomura Holdings Inc. expects initial public offerings to double to their highest level in 17 years as the resurgent stock market attracts investors to entrants, including Japan Post Holdings Co.

The value of debut share sales in the nation may exceed ¥2 trillion in 2015, Nomura IPO head Hiroshi Yoshihara said in a recent interview in Tokyo. Nomura is Japan's biggest equity underwriter.

As many as 100 Japanese companies are preparing to sell shares this year, he said, up from 77 in 2014.