Total proceeds from our ATM added $20 million of equity funding for the full year with all transactions taking place during the first seven months of the year. We minimize short-term borrowing as interest rates increased, and our total cash at year-end was $18 million with $78 million available on our revolving line of credit. Turning to our outlook for Q1 and our expectations for various financial metrics as we enter 2024. As Tom mentioned, with our current visibility, we expect Q1 revenue levels in the $80 million range. This reflects our assumption of a similar level of ATS development revenues, $14 million of tool sales and that Wafer Services will decline to less than $10 million. Given the expected revenue profile, we expect non-GAAP gross margin in Q1 in the low 19% range.
This reflects the greater contribution of tool sales, which we expect will impact gross margin by 200 basis points to 300 basis points. We expect non-GAAP operating expenses of approximately $14 million to $15 million for the first quarter. And beyond Q1, we expect quarterly non-GAAP operating expenses will continue to remain in this range through fiscal 2024. For the full year, we are forecasting another year of revenue growth. We expect customer funding tool investments of at least $60 million and solid growth in ATS development revenue in the range of 10% to 20%. We expect the resulting strong year-over-year growth for our overall ATS business in 2024 will be partially offset by a reduced level of Wafer Services business, which we expect will be down by at least 50% and potentially as much as 60%.
The significant changes in revenue mix for 2024 will impact our gross margin expansion objectives, including tools, but the trajectory is expected to continue to improve. The chief tailwinds for gross margin improvement include the expected continued strong flow-through of over 50% for our ATS development business and the decrease in quarterly depreciation expense as the purchase accounting portion phases out toward the end of Q1. Taking these into account, our expectation is that gross margin for the full year 2024 will increase slightly year-over-year. The higher tool mix is expected to have an estimated impact in the range of 300 basis points to 400 basis points on full year gross margin. There is no doubt that our model is unique and that customer-funded CapEx brings some complexities to modeling our forward-looking financial performance.
However, it’s important to come away from today’s call with an understanding that there is absolutely nothing negative about our customers funding a significant portion of our CapEx needs. First, tool sales to have either a neutral or positive impact on gross profit. We also expect our quarterly depreciation will remain at these relatively low levels as we reach new levels of revenue growth and scale over the next few years. With over 80% of our planned capital expenditures in 2024 expected to be funded by our customers, our foreseeable capital needs are extremely low. And compared to typical foundry models with depreciation totaling at least 15% to 20% of revenues, for us, we expect depreciation will shrink to less than 5% of our revenues as we move beyond Q1, which is one of the reasons we believe we can be so confident in our long-term margin target of 40%.
We also expect to turn the corner to positive non-GAAP EPS in the second half of 2024 and look forward to discussing our success on this key milestone in future calls. With that, I’ll turn the call over to Q&A. Operator, please open the line for questions.
Operator: Thank you. [Operator Instructions] We’ll go first to Quinn Bolton at Needham & Company.
Quinn Bolton: Hey, guys. Thanks for taking the question. Just to start, just for the gross margin outlook, obviously, lots of puts and takes. I understand the tool revenue is a bit of a headwind and the $60 million of tool revenue, understand sort of the drag there. But you’ve talked about Wafer Services being down pretty significantly. And I know that’s been sort of a fab filler. And so can you just kind of talk through the ramp that you see into the second half of the year, what kind of level of gross margin would you expect you need to get to hit that profitability target that you mentioned in the second half of the year? And then I got a couple of follow-on questions as well.
Steve Manko: Go ahead and start with the revenue. I’ll take Wafer Services.
Thomas Sonderman: Yes. So Wafer Services revenue, obviously, is feeling the effects of the overall industry softening. We, of course, have been in a transition mode over the last several years as we continue to bring in more of our ATS development programs preparing them to go to volume production. So as I mentioned in my prepared remarks, we are leaning hard into those transitions. We’re doing this to prepare to not only ramp those into volume as this year unfolds, but more importantly, as we prepare for next year and beyond. And of course, we’re taking into account the fact that lower utilization of our Wafer Services business does have an impact on gross margins, but that is somewhat being offset by the fact that we are bringing in new tools that, while not like a typical ATS development margin, does have an overall positive impact.
