NEW YORK (AFP) - Wall Street stocks finished lower Friday in light pre-holiday trade after Federal Reserve chair Janet Yellen said the plan to raise interest rates this year was on track.

At the closing bell, the Dow Jones Industrial Average stood at 18.234.39, down 51.35 points (0.28 per cent).

The broad-based S&P 500 fell 4.50 (0.21 per cent) to 2,126.32, while the tech-rich Nasdaq Composite Index slipped 0.74 (0.01 per cent) to 5,090.05.

Yellen said delaying a move to raise interest rates "would risk overheating the economy."

However, she also warned that US economy continues to show weakness, with significant job market slack not reflected in the 5.4 per cent jobless rate.

Analysts said trading volume was light Friday ahead of Monday's Memorial Day holiday, when markets will be closed.