How much immigration is "excessive"?
In general, immigration is excessive if it contributes to population growth.
This contribution is measured relative to emigration, and it is sometimes called the migratory increase.
The migratory increase equals immigration minus emigration.
Example: In 2022/2023, about 469k people immigrated to Canada and about 35k people emigrated from Canada.
So, for 2022/2023:
Migratory increase = Immigration - Emigration = 469k - 35k = 434k.
This migratory increase of 434k was very excessive. At the time,
it was greater than the population of Victoria, British Columbia!