document: The economy grew at an annualised pace of 2.1% in the fourth quarter of the year, the Commerce Department said, up from an earlier estimate of 1.9%.
  But the data had little impact on shares, with the Dow Jones up 20.23 points, or 0.1%, at 20,679.55.
  The S&P 500 edged up 2.17 points to 2,363.30 while the Nasdaq added 5.63 points to 5,903.18.
  The biggest faller in the Nasdaq was sportswear maker Lululemon Athletica, which plunged by nearly a quarter after it warned that sales were likely to fall.
  The company said it expected same-store sales to fall in the first quarter of the year, the first decline since 2009.
  Shares in ConocoPhillips jumped nearly 6% after the energy company announced it was selling oil sands and western Canadian natural gas assets to Cenovus Energy for 17.7 billion Canadian dollars ($13.3bn; Â£10.6bn).
  ConocoPhillips is not the first oil major to scale back its operations in the region, with both Royal Dutch Shell and Marathon Oil also having sold oil sands assets.
  The high costs of extraction have made it hard for companies to make profits with oil prices remaining low.
summary: US stocks remained unmoved in early trade, despite an upward revision to the growth rate at the end of 2016.