However, Fonterra sold a total $350 million of bonds which pay annual interest of 4.33%, or 0.75% over the comparable swap rate, when last month its existing $800 million of existing debt matured at a coupon rate of 7.75%.
Craigs Investment Partners broker Chris Timms said the weight of maturities continued this month, with $350 million of CBA capital preference shares redeemed on April 15.
The corporate issues maturing would be dwarfed by the Crown's repayment of more than $11 billion of government bonds but that was not expected to have a noticeable impact on the retail market.
The fixed income proportion of portfolios had been falling due to the negative net maturities and also in response to rising share prices which had prompted increased equity exposures, he said.
''We believe investors are still somewhat reluctantly adjusting to the lower coupons.''
Changing market conditions also meant it was no longer a ''buyer's market''.
Companies were often not paying brokerage on new offers, particularly for vanilla bonds, Mr Timms said.
They still obtained the benefit of accessing retail investors, as they issued in retail-size parcels but, usually, brokerage was charged to the buyers.
Issues of more complex securities, or unrated bonds, which could be deemed to require more investor education, did pay brokerage.
''In addition, we believe the lack of domestic bond issues can be attributed in part to competitive funding markets, both from offshore and banks.''
Companies did not need extra debt and were merely looking to replace maturing debt - usually at significant lower cost, he said.
That was contributing to the contraction in the bonds available on the New Zealand market.
But on the positive side, the credit ratings of many companies were improving, supported by the steady growth in the domestic economy, he said.
That, in part, was justifying the fall in credit margins, although that was more applicable to senior bonds.
''Overall, we believe the availability of corporate bonds has significantly reduced and therefore there is a scarcity value to these assets,'' Mr Timms said.
AMP Capital New Zealand head of fixed income Grant Hassell said there would be more retail investors looking for new places to park their funds this year.
Nearly $3 billion of high-coupon retail corporate bonds was set to mature this year with a weighted average coupon of 7% and little prospect of finding comparable returns, given falling interest rates.
