Rt Hon JACINDA ARDERN: Because, as the member has pointed out in the question, one of the reasons it's been used as a diagnostic tool is simply to ensure that we can get the scale, reach, and immediacy for this period of the outbreak. In the beginning, of course, we were continuing to run an elimination strategy, which meant precision was key. We're now at a point where we're continuing to manage down as much as possible, to reduce the impact on the health workforce, so it means you have a greater tolerance for the fact that rapid antigen testing has an error rate of between 80 percent and above. For surveillance, it's because of that error rate that you do rely on using them for those that you've identified as household contacts or for those who are symptomatic.