Shares in Facebook have dropped again as investors continue to shun what was one of the most-anticipated flotations.
In mid-morning trading the shares were about 2.3% down at $33.27 each, having fallen 5.2% at the open.
Facebook debuted on the Nasdaq stock exchange on Friday at $38 a share in the world's third-biggest flotation.
But the shares fell 11% on Monday, and the continuing lacklustre performance has intensified debate over whether Facebook was over-valued.
It is a remarkable turnaround from recent weeks, when the social network's share sale was over-subscribed and the eight-year-old firm was valued at $104bn (£66bn).
But some analysts say the fall is of little consequence in the early days. "Whether [Facebook] is worth $95bn or $100bn, it's immaterial," Jeremy Liew of investment company Lightspeed Venture Partners told Reuters.
The social networking site has transformed the way in which hundreds of millions of people around the world communicate. It is also transforming the way companies advertise to existing and potential customers.
But Facebook's 900 million users helped the company generate just $1bn in profit last year, and there are concerns about its ability to grow profits in the future.