A financial review of the 14 ITM Cup rugby unions suggests falling revenues are threatening the future of the game.
The review, carried out by Deloitte, shows their collective revenues have dropped nearly 20% over the last five years.
The review says a total loss of $16 million since 2007 is largely due to a reduction in match-related revenue, such as gate takings and hospitality.
New Zealand Rugby Union chief executive Steve Tew says that is no surprise and unions are adjusting their behaviour accordingly.
Deloitte partner Grant Jarrold of Christchurch says the falling revenues are threatening the game's future.
He says if the unions cannot survive, then the development of rugby at the grass roots will struggle.
The Rugby Players Association says a business approach is needed to turn around the fortunes of the provincial sides.
Chief executive Rob Nichol told Morning Report that teams need to get people back through the turnstiles, as revenues were hit last year by fans saving money for World Cup tickets.
One union still making money is the Tasman Rugby Union, which has recorded a profit for the last three years.
Chief executive Andrew Flexman says the union has adopted a culture of spending within its means.
He says financial success is dependent on sponsorship deals, which are getting harder to obtain, more spectators through the gates and success on the scoreboard.