This is an issue that we consider at the end of each fiscal year, or rather when the books for a fiscal year are provided to us. Every year, some departments, particularly those with large budgets, such as Aboriginal Affairs and Northern Development Canada and Indigenous Services Canada, don't spend all the funds allocated to them. That's largely due to the fact that, during the fiscal year, they don't have the capacity to spend their entire budget, which is not unusual for departments. In fact, they are reprimanded very harshly if they spend more than the budget allocated to them, and that forces all managers to be cautious.
The two departments that deal with Indigenous issues and provide services to Indigenous people tend to have more unspent funds than other departments because of the size of their initial budget.
So the answer to your question is yes, and it's a recurring phenomenon.