Thank you for the question. I'm happy to do that at a high-level, in broad terms.
Over the course of the pandemic, it was necessary for the government to issue a lot of debt to fund COVID emergency response programs and to fill in gaps from the interruption of revenues over the course of the pandemic and, obviously, the economic contraction through 2020 and into 2021.
The government had committed to funding this debt program through the extension of the term structure of the debt, edging more into the long end of the yield curves with longer duration bonds. You see that reflected in the debt management strategy.
As interest rates are at historic lows—albeit creeping up gradually as the economy strengthens—a bulk of the debt was funded at the long end, so you see that reflected in the chapter you referenced.