Yes, so stock based comp in 2021, again, as I mentioned, I think that's going to be close to $10 million, call at $9 million, or so in contribution. So, absent that stock based comp, you're talking $10 million lower. So $70 million, $75 million or so to $80 million. And in terms of the stock based compensation in 2020, it was relatively low, absent Q4, where we did see a significant contribution primarily from the ESPP program. And, of course, this is all related to the very rapid appreciation of our stock price. So, again, I would take out about $9 million from our 2021 OpEx, and that's what it would have been without this non-cash charge. Now, in terms of where the office spend is going to go, I would think about a few million dollars step up sequentially between the $16.4 million that we did in Q4, and what we think we'll do in Q1, and that initial step up is, again, public company costs and incremental stock based comp charges. And then, I would expect to see a continued slight increase in OpEx through the remaining three quarters of year. And that OpEx is primarily driven by an increase in personnel-related expenses, much of which is related to expansion of our commercial organization or commercial infrastructure, as well as some G&A. And then, on the R&D front, spend in towards our clinical study costs associated with AeriSeal, again, increasing through the back part of the year, is a major driver for that expense.