Benchmark 10-year U.S. Treasury yields finished slightly higher Tuesday, as investors sold haven government debt ahead of a planned signing of an partial U.S.-China trade deal.

Bond and stock markets will be closed on Wednesday for New Year’s Day on Wednesday.

The 10-year Treasury note yield TMUBMUSD10Y, 0.679% gained 1.5 basis points at 1.909% Tuesday, while marking the largest 1-year yield decline for benchmark government paper since December 2014, according to Dow Jones Market Data.

The 2-year note rate TMUBMUSD02Y, 0.133% shed 1.2 basis points at 1.559% Tuesday, sealing its largest 1-year yield decline since December 2008.

On Monday, the widening yields between the two maturities briefly steepened the yield curve to around 34 basis points, its most positive levels since October 2018. A steeper curve can indicate brewing expectations for a bump in economic growth and inflationary pressures.

Meanwhile, the 30-year bond yield TMUBMUSD30Y, 1.436% added 3.6 basis points at 2.378%, which also was its largest 1-year yield decline since December 2014.

For the 2010 decade, benchmark 10-year government paper fetched an average yield of 2.396%, down from 4.45% for the 2000s, 6.667% for the 1990s and 10.59% for the 1980s, according to Dow Jones Market Data, which was the first decade it began recording Treasury market data.

What drove Treasurys?

Bonds and stocks over the past several weeks mostly have been taking their cues from reports on a phase-one U.S.-China trade deal, which has helped to boost forecasts for global economic growth. Investors have recently sold bonds and the U.S. dollar in anticipation of a deal between Beijing and Washington being struck.

Indeed, early Tuesday, President Donald Trump via Twitter said he would sign a so-called “phase one” trade deal with China at the White House on Jan. 15 and that he will head to Beijing to begin negotiations on a second phase of Sino-American discussions.

The President’s comments came moments before White House adviser Peter Navarro described a signing of the partial resolution as “in the bank,” during a CNBC interview.

In economic data, confidence in the U.S. economy ended 2019 higher than at the beginning of the year, according to a new reading of the U.S. Conference Board’s index, even though future expectations are for economic growth to be flat in the first half of 2020.

Fixed-income markets also have been responding to the Federal Reserve’s expansion of its $4 trillion balance sheet to support short-term money markets and foreign investment in bonds, amid worries about flagging global economic growth.

But low government bond yields also have given a lift to other haven assets, with gold for February delivery US:GCG20 on Comex settling at $1,523.10 an ounce Tuesday for an 18.9% annual gain, its strongest year since 2010, according to FactSet data.

What did market participants say?

“Whether its due to the Fed’s expansion of their balance sheet, the ever growing US deficits (both trade and budget), the rise in yields overseas, or other things, I do believe this will be a key story in 2020. And if correct that the dollar continues to weaken, the flow impact could be large,” wrote Peter Boockvar, chief investment officer at Bleakley Advisory Group, in a Tuesday research note.

“To name a few, foreigners have piled into US corporate credit markets on an unhedged basis and just recently unhedged in the US Treasury market who will both get squeezed and could reverse with higher US rates,” he said.

But Robert Tipp, chief investment strategist at PGIM Fixed Income, thinks that global bond yields will likely trend lower in 2020, even though market participants have been pricing in some European rate hikes, he told MarketWatch in an interview.

“You’re going to see, in our estimates, global yields remaining incredibly low and keeping a cap on [10-year] U.S. Treasury yields in the 2% or, at most, 2.25% level,” he said.