NEW YORK, Jan. 2 (Xinhua) -- U.S. stocks opened higher Tuesday, the first trading day of 2018, as Wall Street looks to start off the new year on a high note.

Analysts said optimism over U.S. markets has been rising despite valuations that are seen as stretched by many measures.

On the economic front, the country's manufacturing purchasing managers' index (PMI) data is scheduled for release later in the morning.

U.S. stock markets were closed Monday for the New Year's Day.

U.S. stocks had a banner year in 2017, with all three major indexes posting their best annual gains since 2013 and notching all-time highs.

The broader S&P 500 surged about 19.4 percent last year, with technology and consumer discretionary the top two performers.

Shortly after the opening bell, the Dow Jones Industrial Average rose 128.39 points, or 0.52 percent, to 24,847.61. The S&P 500 added 12.18 points, or 0.46 percent, to 2,685.79. The Nasdaq Composite Index gained 35.75 points, or 0.52 percent, to 6,939.14.

U.S. stocks ended lower Friday, with very thin trading volume, as investors prepared for the New Year holiday. Enditem