New Zealanders may have won more than $347.7 million in Instant Kiwi prizes over the past five years, but the popular scratchcards have played a key part in the "normalisation of the problem," the Gambling Foundation says.
Figures released under the Official Information Act reveal the amount won from Instant Kiwi tickets has risen from $59 million in 2007-08 to $90.7 million in 2011-12.
The number of winners has increased from 9.5 million (2007-08) to 11.7 million (2011-12), with the average winning ticket increasing from $6 to $8.
While the number of games had decreased over the same period from 51 to 37, there had been a move to more expensive tickets with the first $20 Instant Kiwi introduced in 2011-12.
Over those five years the value of unclaimed prizes or games withdrawn from sale was $22 million.
A NZ Lotteries spokeswoman said once an Instant Kiwi was withdrawn from sale customers had to claim any prize.
Unclaimed prizes entered a Prize Reserve Fund, used to fund special prizes and augment prize pools for various draws and games, she said.
NZ Lotteries, which launched Instant Kiwi on September 14, 1989 had never withdrawn an Instant Kiwi game from sale with all top prizes remaining, she said.
Those customers wanting to know how many prizes remained in any game could ask at a Lotto kiosk for a print out, she said.
Problem Gambling Foundation chief executive Graeme Ramsey said Instant Kiwis were of "the more dangerous end of the NZ Lotteries product suite".By Hamish McNeilly