Sure. So a couple of things. Yes, cash burn guidance is 40 million on average for the year, Q1 will be higher due to bonus payouts. We had a pretty low quarter in the fourth quarter. There was favorable working capital, low CapEx spending and high investment income. So we're coming off a low burn on the fourth quarter, but 1Q will be a pretty significant step up. If we look at kind of total OpEx, overall, we spent just over 385 million, including cost of revenue last year. Some of the areas, we've talked about in prior calls where clono enhancement, leveraging lower sequencing costs, DNA extraction costs, cloud compute, real estate, these are all ongoing initiatives. We've done a lot of work around R&D, as well. We've mapped projects to revenue, our margin enhancement opportunities. And there's some leverage there that we've seen. Similarly with G&A. And then, we're doing a lot of work on gross margins. Now, we'll have more to say on that, at some point in the future, but this is an area where we do see significant potential, as we scale. So, the important thing about OpEx is, it's not coming from a single area, it's all parts of the company, there's been a real cultural shift underway here at Adaptive and really, there are no sacred cows. So we continue to look for opportunities to get more efficient and better as a company going forward, but it's across all parts of the business.