Twitter held its initial public offering last month at $26. Since then the stock has increased by 169%, valuing the company almost $40 million. Investors are confident that Twitter can attract more money from ads as evidenced by the fact that its sales growth exceeds that of competitors like Facebook and Google.

Twitter Inc. (TWTR), the microblogging service that held its initial public offering last month, rose to a record for a third trading day amid optimism that the company has room to expand sales in digital advertising. Twitter jumped 8.4 percent to $69.96 at the close in New York after rising 7.5 percent yesterday. The stock has surged 169 percent since going public at $26 on Nov. 6, giving Twitter a market value of almost $40 billion — larger than Time Warner Cable Inc., media company Viacom Inc. and retailer Target Corp.