Google Inc.’s stock price dropped by more than 4 percent Monday, accelerating a recent shift in sentiment that has caused once-ebullient investors to become more circumspect about the online search engine leader.Barron’s cast the latest pall on Google with an article outlining several risks that threaten to squeeze the company’s profit margins and cut its market value in half.The gloomy scenario further dampened investors’ enthusiasm for Google, whose market value has plunged by 27 percent during the past month to wipe out nearly US$40 billion (euro33.65 billion) in shareholder wealth. Google’s shares fell US$16.91, or 4.7 percent, to close at US$345.70 on the Nasdaq Stock Market. The shares peaked at US$475.11 on Jan. 11. For more click here.