So, when I think about population health, you mentioned earlier that a health insurance company can either try to manage it for the provider or teach the provider to manage it themselves. There's also a hybrid approach where they work together. Which method is more effective? Is it having the health insurance company build a population health overlay and target and sign up people for clinical programs in the market, or is it more efficient to work closely with the primary care provider? If you do work closely with the primary care provider, should they be the ones targeting people for clinical programs, or should the health insurance company retain that role and just coordinate better with the primary care provider?

To give you some data points, Optum's programs, which I call point solutions, such as diabetes management or transitions of care, typically see a 7% to 10% engagement rate with their patients.For every 10 patients they call, maybe one out of those 10 picks up the phone and engages with them. These programs operated independently of the primary care office. The last pilot I did, now branded as Optum Practice Extend, was highlighted at United's investor conference last year with strong results. This model, as I mentioned earlier, involves calling on behalf of Doctor Smith's office, informing the patient that Doctor Smith asked us to call because they are not taking their medications, for example. We always disclose that we are calling from United and explain the program. This approach has seen an engagement rate north of 55% to 60%, with one out of two people engaged in the conversation.