LinkedIn, the business networking Web site became the No. 2 social-networking service in the US last month, boosted by its initial public offering in May.

The company had 33.9 million visitors in June, up 63 percent from a year earlier according to a ComScore report released Friday.

Shares of LinkedIn rose $5.62, or 6 percent, to $99.60 in Friday’s trading. The IPO priced the shares at $45.