Robinhood Falls in Debut as Retail Investors Keep Distance (3)

Robinhood Markets Inc. ended its first day as a public company 8.4% below its initial public offering price after failing to win over some of the very retail investors it’s courting for long-term growth.

The online trading platform focused on making investors out of millennials slid as much as 12% in its trading debut Thursday after a $2.1 billion IPO priced at the bottom of a marketed range.

The shares, which opened at the $38 offer price, closed at $34.82 in New York, giving the company a market value of $29 billion. Accounting for employee stock options and similar holdings, ...