In a note released yesterday, Fitch Ratings has affirmed its long-term and short-term issuer default ratings for the New Zealand Association of Credit Unions (trading as Co-op Money NZ), set at BB+ and B, respectively, in the face of expected flat profits in 2017 and other limitations to Co-op Money NZ's growth prospects.Co-op Money NZ is primarily a trade organisation and service provider to its members, offering sector support, central banking services, IT support and payment solutions with scale benefits that members cannot achieve individually.Although it serves all the credit unions and building societies in New Zealand, the combined market share of its members is low relative to the financial system."Geographical concentration and limited financial flexibility also means it is unlikely to reach investment grade ratings," was the Fitch view.The rating agency also said that the level of performance over the next year or two for Co-op Money NZ's ratings would be constrained by its moderate franchise and small customer base. At the end of the financial year to June 2016 (FYE16), the provision of central banking services accounted for the majority of Co-op Money NZ's balance-sheet assets and non-equity balance-sheet funding. Fitch said it expected Co-op Money NZ's profitability to remain flat in FY17 and said its capitalisation was "adequate for its size and operations".