It's a mix of both. My colleagues from the Department of Finance can weigh in, but we have discussions on a regular basis with departments on their forecasts for the year and on how they are actually coming along. Usually partway through the year, you have a discussion about whether, if they're not going to spend it this year, they can spend it in a future year or whether we are going to withhold it in the centre. There's a mix of both.
What you really have to get to is the results around what their spending was—was it projects that didn't occur, or have they actually come in under budget, as you mentioned? It's those discussions around their forecasts that drive it.
The key public document is the quarterly financial statements that departments produce, but frankly, nobody looks at those. They're out there, and you can get some sense of departmental spending. They're public. Internally we have different conversations about what their projected spending is. The quarterly one says what they've spent; internally we have discussions about their projected spending.
Partway through the year you would see the government come in with supplementary estimates, if cases of increased spending are planned, but they don't come in with decreased spending. It's really a forecasting piece.