NEW YORK (AFP) - Wall Street stocks finished a strong week on a mostly positive note, with the Dow and S&P 500 rising modestly and the Nasdaq dipping.

The Dow Jones Industrial Average rose 0.4 per cent to close the week at 24,831.17, its seventh straight positive finish.

The broad-based S&P 500 advanced 0.2 per cent to end at 2,727.72, while the tech-rich Nasdaq Composite Index slipped less than 0.1 per cent to 7,402.88.

Analysts said a combination of mostly good corporate earnings and mild inflation had boosted confidence, allowing investors to look past myriad lingering risks on trade, monetary policy and US politics.

Major indices rose more than 2 per cent for the week.

"Good earnings and mild inflation numbers are a great formula for the markets," said Jack Ablin chief investment officer at Cresset Wealth Advisers.

Health and pharma shares rose after analysts concluded President Donald Trump's plan to address high drug prices would not significantly affect industry profits. Merck rose 2.8 per cent, CVS Health 3.1 per cent and Express Scripts 2.6 per cent.

Cybersecurity company Symantec lost more than one third of its market value on Friday after it disclosed an internal probe that may lead it to restate results, and refused to take questions from analysts.

Symantec said its audit committee had retained independent counsel and that it "voluntarily contacted" US securities officials about the probe.

Dow member Verizon gained 3.1 per cent following an upgrade from JPMorgan Chase.