Yeah, Lisa, I'll start and I know others will jump in here. Thanks for the question. But, Lisa, it is true that as we stated in our prepared remarks that more of the value of negotiated rebates are being passed back to clients. And keep in mind, we've been saying for a while now that we have different flavors of contracting where we've had clients for a while now that prefer to have 100% of that rebate value passed back. So that is a trend that has continued. And again, as we said, we underwrite our PBM contracts to an overall level of profitability. So, Lisa, if you triangulate all of the numbers that we threw out there for 2018 that rebate pass-through is closer to 98%, okay, than some of the others that we had historically talked about. Lisa, your second question around interaction with the administration, we have had productive engagement and discussions with the administration, on the Hill, at the secretary's office. And I do believe for reasons that we talked about and reasons that you see outlined in the President's blueprint, there is an acknowledgment as to the role that PBMs play. And again I think yesterday afternoon's CMS announcement is just another example of that. So I'm sure those conversations will continue. And, Lisa, I think that as we talked again in the prepared remarks, this über focus on rebates, what we believe, Lisa, wherever we end up because the administration hasn't finished the story in terms of what their desire is on rebates, but what will not go away is the ability for PBMs to use size, scale, competition, private sector innovation to garner discounts that lower the cost of medications for clients and their members.