* Dow less than 15 points away from 20,000
* Twitter falls after CTO announces departure
* FedEx lower after results fall below expectations
* Indexes down: Dow 0.01 pct, S&P 0.05 pct, Nasdaq 0.04 pct (Updates to open)
By Tanya Agrawal
Dec 21 (Reuters) - U.S. stocks opened little changed on Wednesday, with the Dow Jones Industrial Average still flirting with the elusive 20,000 mark, a day after both it and the Nasdaq Composite hit record highs.
The Dow, first calculated in 1896, was less than 15 points away from the historic level. The blue-chip index has been threatening to breach the mark for the last several days, but has failed to do so.
U.S. stocks have been roaring ahead since the election, with the Dow up 9 percent and the S&P 500 6 percent on bets that President-elect Donald Trump's plans for deregulation and infrastructure spending will boost the economy.
"We're looking at a relatively quiet morning as investors wind down ahead of the holiday weekend," said Andre Bakhos, managing director at Janlyn Capital in Bernardsville, New Jersey.
"The market has been rallying since the election and these minor pauses are welcome and necessary as traders take some profit."
Still, there are concerns that the recent rally has made stocks too expensive. The S&P 500 is trading at about 17 times expected 12-month earnings, well above the 10-year average of 14, according to Thomson Reuters Datastream.
Volumes have been muted in the last full week of trading before the year-end holiday season, subjecting the market to pronounced movements amid a lack of any major economic data.
At 9:38 a.m. ET (1438 GMT) the Dow Jones industrial average was down 1.26 points, or 0.01 percent, at 19,973.36.
The S&P 500 was down 1.23 points, or 0.05 percent, at 2,269.53.
The Nasdaq Composite was down 2.26 points, or 0.04 percent, at 5,481.68.
Six of the 11 major S&P sectors were lower, with the financial index's 0.24 percent fall leading the decliners.
Oil edged up, driven by expectations for a decline in U.S. crude inventories and bringing price gains for December to 10 percent.
Scheduled economic data includes existing home sales for November, which likely dropped 1 percent to an annual rate of 5.5 million. The data is expected at 10 a.m. ET.
Twitter fell 3.4 percent to $17.32 after its chief technology officer said he would be leaving the company, the latest in a string of high-profile executive departures.
FedEx fell 1.8 percent to $194.92 after the package delivery company's quarterly results missed expectations.
Accenture fell 4.1 percent to $119, after the consulting and outsourcing software services provider's revenue forecast missed estimates.
Chipmaker InvenSense jumped 17.6 percent to $12.74 after people familiar with the matter told Reuters that Japanese electronic parts maker TDK Corp is in talks to buy the company.
Advancing issues outnumbered decliners on the NYSE by 1,413 to 1,172. On the Nasdaq, 1,117 issues fell and 1,108 advanced.
The S&P 500 index showed eight new 52-week highs and no new lows, while the Nasdaq recorded 60 new highs and 11 new lows. (Reporting by Tanya Agrawal in Bengaluru; Editing by Anil D'Silva)