US markets hit record highs on Thursday, boosted by optimism over a US-China trade deal and positive sentiment on Wall Street as 2019 drew to a close.

The Dow Jones Industrial Average, S&P 500 and Nasdaq set new records on Thursday, exceeding expectations of the traditional year-end “Santa Claus” rally as 2019 gains showed no signs of abating.

The Dow was up 76 points at 28,592, while the S&P 500 and the tech-heavy Nasdaq Composite were both up about 0.4% at all-time highs.

The gains, on thin trading volumes with markets still closed in Europe, Australia and Hong Kong, came as Amazon shares climbed 1.8% after the e-commerce company said the holiday shopping season had broken all prior records, rising 19% over the period.

Markets also responded to upbeat news on the US-China trade talks, after China’s commerce ministry said it was in close contact with Washington over a deal. On Tuesday, Trump said a deal with Beijing was “getting done”.

Optimism over a deal also moved oil prices higher. Benchmark Brent crude was up 49 cents, or 0.7%, at $67.73 a barrel, while West Texas Intermediate was up 52 cents or 0.8% at $61.63 a barrel.

US stocks remain the leading performers for the year. The S&P 500 has risen 2.6% this month and 8.2% this quarter, bring the year-to-date gains to 28.6%. The index is 1% off its best annual performance since 1997.

Through the first 51 weeks of this year, the Dow is up by about 24%.

“Stocks look like they just wont quit. The rally is for real,” Chris Rupkey, chief financial economist at global financial group MUFG, said in a note on Thursday. “The economy’s engines continue to hum.”