Newshub will be fact checking key statements from both leaders in the Leaders Debate on Monday night.

Claim: National says Labour missing $11.7b from its fiscal budget

In a juicy pre-debate claim, National's Finance Minister Steven Joyce attacked Labour's fiscal plan, claiming it contained four basic errors that could add $11.7 billion to New Zealand's debt, over the next five years.

Is Mr Joyce correct?

Working this out requires some serious number crunching - have a go yourself:

Essentially Labour and its independent financial advisor BERL say National has exploited a difference in accounting methodology to misrepresent its figures. And several independent commentators are in agreement.

BERL executive director Ganesh Nana issued a statement disputing that there were errors: "The alleged 'hole' is a fiction arising from a disagreement over definitions."

In The Spinoff, data expert Keith Ng said the "money was accounted for" and that Labour had recorded the missing money behind individual line items.

Writing for Newsroom, Bernard Hickey said "there is no hole in Labour's fiscal plan".

During the debate, Ms Ardern backed her Party's plan, but Mr English took aim, claiming: "The numbers don't add up, and this is why. When you look at how they've calculated things, what they've done is this: Let's say the police get a pay increase… what they've said is we've got enough money to pay it for one year, but not for the years after.

"So they just haven't rolled it out. And that means, the effect of it is, why they've allocated money to health and education, they haven't got anything left for anything else… they have to fill the gap with higher taxes, which I feel would now be inevitable under Labour."

The verdict: There is no $11.7b hole in Labour's fiscal budget, at least as far as we can tell

Claim: Bill English said house prices are falling in Christchurch

They are actually still rising, but only by a mere 0.1 percent over the past year according to a report four days ago by Quotable Value.

But a report in June from Monitoring Greater Christchurch Regeneration says housing affordability in greater Christchurch has been improving since 2014.

So compared to Auckland, Christchurch is very affordable and faring much better in the so-called housing crisis.

The verdict: Mr English was almost correct

Claim: Jacinda Ardern says there are 290,000 children living in poverty in New Zealand

Unicef New Zealand says there are actually more, some 295,000 Kiwi children living in poverty.

That's 28 percent of all New Zealand children.

The verdict: Ms Ardern was correct, but could have put her figure even higher

The claim: Bill English said New Zealand has the fifth lowest gender pay gap in the world

The gender gap in New Zealand is indeed very low when compared to other OECD nations.

The latest figures from the OECD show New Zealand had a 6.08 percent gap in 2014, and only Belgium (5.91) and perhaps surprisingly Italy (5.56) were lower.

The verdict: Mr English was probably correct

The claim: Bill English said wages are going up in New Zealand under National

Figures released by Stats NZ show wage inflation in all sectors has seen a 1.6 percent rise over the past 12 months, while average ordinary time hourly earnings are up by 1.5 percent.

The verdict: Mr English was correct, wages in New Zealand have increased, but not by a huge margin

The claim: Ms Ardern is promising a 50-50 split of men and women in her caucus

Labour's shadow cabinet only has eight women compared to 14 men - so only 35 percent.

So while a 50-50 split would be unattainable for a Labour cabinet, Ms Ardern's goal of filling her caucus with 50 percent women could be possible if she shuffles her cards accordingly.

The verdict: You'll just have to wait and see

Newshub.