One of the biggest global issuers of New Zealand dollar denominated debt, or Kauris, the World Bank, says interest in the Kauri market from central banks is growing, particularly in Asia.
The International Finance Corporation (IFC) is part of the World Bank group which focuses on private sector lending and investment in emerging markets.
The IFC entered the Kauri market in 2007, and has issued bonds every year except 2008.
The IFC's total debt issuance programme for the 2013 financial year was about $13 billion, and Kauris made up about 6 percent of that.
It also issued about $50 million of debt in New Zealand dollars, or uridashis to Japanese retail investors who want exposure to the New Zealand dollar.
The Reserve Bank said in its March Monetary Policy Statement that issuance of Kauris was strong at $2.3 billion for the first two months of 2014, more than $5 billion than was issued for the whole of last year.
Because the issuance of Kauris requires buying the local currency, the more issues there are, the more upward pressure there is on the kiwi dollar.
IFC head of funding Ben Powell said the reason it loved the Kauri market was that there was consistent demand for them in New Zealand.
He said the largest investor was the banks, then some of the asset managers and insurance companies.
"We don't have the same real depth in terms of some of the asset managers that are active in Aussie dollars, but you do have that consistent appetite from the banks in New Zealand, I would say that's the core investor base for us and has been since we started issuing."
Mr Powell said there has been growing interest from central banks, particularly Asian central banks, which view New Zealand as having a strong currency and a fiscally prudent conservative government.