I will speak to that, and then, Matthew, you can add if there's anything else.
Our consumer price index is one of our critical products. We put in a lot of effort into make sure it's of the highest quality.
What you're talking about is the substitution effect. We used to have fixed baskets every two years, and we would revise the weights, but, to account for the substitution effect, we've moved to an annual basket so that we account for that substitution more frequently.