"I'm sure my notes said 1.2 billion but that's okay, I'm happy to be corrected on that," he said, adding that he would double-check the figure himself.
"It's a large number, anyway. Whatever it is, it is a strong component of our economy moving forward."
When he was next given an opportunity to speak, about 15 minutes later, he confirmed the 1.2 million figure was correct.
Labour candidate Stuart Nash also had problems with numbers at the meeting - although his mistake appeared to be a deliberate attempt to charm the elderly audience rather than genuine confusion.
"I thought, Grey Power, you had to be over 55? Because there aren't many people here over 55, are there?" After groans from the crowd, Mr Nash added: "Look, it's election time, there's three days to go."
Greens candidate Paul Bailey suffered his own awkward moment at the meeting when he said the level of crime in the region did not make him feel fearful.
Mr Bailey was jeered for saying "statistically, the changes of anything happening are pretty remote," and was told that was because "you're a man".
The candidates could take heart that any gaffes at the meeting will not have influenced as many attendees as it might have first appeared.
When asked by Grey Power Napier and Districts secretary Maxine Boag how many of them had already voted, about half of the 100 people at the Tamatea Community Church put their hands up.
A fourth candidate standing in Napier, Garth McVicar, attended the meeting but was not permitted to speak.
Ms Boag said earlier this week Mr McVicar's Conservative party had presented at the organisation's meeting for minor parties, held last month, and it would be unfair if he was given a second opportunity, even though he has been polling highly.
That decision was unsuccessfully challenged by a member of the audience yesterday.
One issue Mr McVicar has campaigned strongly on - police resourcing in Napier - was well debated by the three candidates who spoke.
Mr Walford said allocating police resources in the district was up to the local district commander.
"I don't think you want the Government messing with that level of management.
"The Government's role is to create the environment for things to happen and incentives to minimise crime," he said.
Mr Nash said he had been in regular contact with police over the resourcing issue and management had said the Napier station would not close.
He remained concerned, however, about the risk of police losing non-sworn staff who carried out vital back-room work.
"[Staffing] is not at the level we need or we expect in Hawkes' Bay and something does need to be done about it," he said.