A global economic upswing helped the value of assets at central banks, sovereign funds and public pension funds hit $38.7 trillion in 2017, according to new research by London-based think tank OMFIF.

That was a 7 percent rise of $2.5 trillion, with public assets totaling $36.2 trillion in 2016. The organization said it was the largest jump it had seen in the five years it's been tracking global markets.

Equities across different global indexes hit all-time highs in 2017. In the U.S. in particular, shares were supported by strong earnings, solid economic data and tax changes. The S&P 500, Dow and Nasdaq gained 19.4 percent, 25.1 percent and 28.2 percent, respectively, during the year.

"Assets were boosted by the continued global economic recovery, particularly across advanced economies," the authors of the study said.

Between the three different institutions, pension funds recorded the highest asset increase, up by 8.1 percent on the year to $1.1 trillion. Central banks' assets rose 7.8 percent and sovereign funds' were up by 5.1 percent.