Global reserve managers expect 8.5 percent of foreign reserves to be invested in renminbi by 2020, according to a recent survey sponsored by HSBC, an international banking and financial services institution.

The number went up from a previous forecast of 6.9 percent by 2020, made by global reserve managers in 2015.

The renminbi is seen as more attractive compared to a year ago by 74 percent of reserve managers in the HSBC survey — the highest among major currencies, followed by the US dollar and the euro.

The study includes 79 reserve managers worldwide who are responsible for $5.5 trillion in total reserve assets, 54 percent of the world total.

"The survey confirms the continued momentum of renminbi. Respondents on average predicted it will reach 8.5 percent of global reserves by 2020 — which would represent a very large increase from the latest IMF published level of 1.2 percent as of the end of 2017," said Christian Déséglise, global head of central banks at HSBC.

Helen Wong, HSBC's chief executive for China, said: "It is encouraging to observe the growing optimism in the renminbi among reserve managers at central banks around the world, as China steps up the opening up of its capital markets and in the process makes its currency more investment-friendly. The recent addition of mainland China-listed A shares into MSCI's Emerging Markets Index, China's policy incentives to encourage cross-border use of the Chinese currency and the future inclusion of Chinese bonds into global indices are set to further stimulate renminbi demand from international investors."

Though positive overall, some said it will take time for many asset managers to fully embrace renminbi as one of their main reserve currencies. Issues like market breadth and corporate governance remain critical.