I think that's an excellent question.
As I mentioned, at the beginning it was simply contact tracing and the ability to get basic traveller information to the provinces. Eventually we added the capture of pre-arrival testing—PCR, rapid testing or whatever it was at the time. We put that in, and eventually the vaccine certificates.
Every country did it completely differently. For some countries, it was very basic optical character recognition. It would be uploaded, and we would capture that it was, for example, a Moderna vaccine. There was some basic information there for us. Others were much more sophisticated.
As I said earlier, because of the QR code that we had with provincial health care authorities in Canada, we had a very high degree of confidence in that information, and many Canadians came across the border and were never asked for—