UPDATE 3-McDonald's robust U.S. sales fail to impress, shares fall

(Recasts, adds context and analyst commentary)

Jan 30 (Reuters) - McDonald's Corp on Tuesday reported robust U.S. fourth-quarter restaurant sales, boosted by new buttermilk chicken tenders and cheap value offerings, but that was not enough to match Wall Street's increasing appetite for growth.

Investor expectations are high three years into a turnaround led by Chief Executive Steve Easterbrook. Under his guidance, the company is recapturing share from rivals and winning back customers who had defected to fast-casual chains like Panera Bread and Chipotle Mexican Grill Inc.

Shares in the world's biggest restaurant chain fell 0.6 percent to $176.63 in morning trading. They have climbed 80 percent since Easterbrook was named CEO on March 1, 2015, outperforming a 36 percent rise in the S&P 500.

McDonald's is now doubled down on discounting, piling more pricing pressure on rivals with a $1, $2, $3 menu launched earlier this month. It also plans to invest $2.4 billion this year to help open 1,000 new restaurants and renovate and modernize existing units to accommodate self-service kiosks, mobile ordering and delivery.

Sales at U.S. restaurants open at least 13 months jumped an enviable 4.5 percent, the fourth straight quarterly rise, but that only matched analysts' estimates. Sales in the region were boosted by higher demand for its McPick 2 $5 combo offer and cheap drinks. The United States is McDonald's biggest market in terms of restaurants, revenue and operating income.

Global same-store sales were up 5.5 percent, as it served more customers in regions including Canada, the United Kingdom and China. That exceeded the 5 percent gain analysts expected, "though a bit more modestly than in previous quarters," Bernstein analyst Sara Senatore said in a client note.

Net income fell to $698.7 million or 87 cents per share, from $1.19 billion or $1.44 per share, a year earlier, mainly due to a $700 million one-time net charge related to recent changes in U.S. tax law.

Excluding items, the company earned $1.71 per share, beating the average analyst estimate of $1.59, according to Thomson Reuters I/B/E/S.

After crunching the numbers to account for the tax charge and a lower-than-expected effective rate in the fourth quarter, Cowen & Co analyst Andrew Charles said in a client note that he viewed the underlying earnings per share as in-line with expectations.

Revenue fell 11.4 percent to $5.3 billion in the quarter ended Dec. 31 as McDonald's stepped up sales of restaurants to franchisees and strategic partners. (Reporting by Siddharth Cavale in Bangalore and Lisa Baertlein in Los Angeles; Editing by Meredith Mazzilli)