Does the Northern Ireland draft budget stand up?
The Executive's budget is in response to £4bn being taken out of the local economy in the next four years.
It is based on the principle that the more money the Executive can generate the less departmental budgets will fall.
All government departments are expected to see falling revenue over the next four years, with the exception of the core health service budget, which will see a marginal increase in real terms.
To prevent even more money leaking out of the kitty, the Executive's plan is to raise £840m from new income streams. The more successful it is at this, the less departmental budgets will drop.
Some of these specific new methods of income generation have figures attached to them, but others don't.
Housing Associations will be asked to cough up £20m a year from the next four years from their savings, and the Harbour Commissioners will face a £35m levy on their reserves.
On top of these is the most eye-catching proposal of all - a plastic bag tax of 15 pence a bag. All told the Executive believes it will be able to raise about £300m from these sources.
But the most intriguing question is where will the remaining £540m in new income come from? It's not money that is currently sitting in some bank account somewhere.
Instead it is projected and is so far aspirational.
According to Stormont officials, the £540m will be realised "from the disposal of assets". When pushed they say it will mean land and buildings being sold off.
A key question, though, has to be, can that money be realistically achieved? Especially in the worst property slump seen in decades.