impairment, the cumulative drilling costs incurred to date for such property and all or a portion of the associated leasehold costs are transferred to the full cost pool and are then subject to depletion and the full cost ceiling test limitation.
Depletion on oil and natural gas properties was $5.3 million and $3.9 million for the three months ended September 30, 2024 and 2023, respectively. During the three months ended September 30, 2024 and 2023, the Company incurred development capital expenditures of $1.0 million and $1.5 million, respectively.
At September 30, 2024, the ceiling test value of the Company’s reserves was calculated based on the first-day-of-the-month average for the 12-months ended September 30, 2024 of the West Texas Intermediate (“WTI”) crude oil spot price of $79.40 per barrel and Henry Hub natural gas spot price of $2.21 per MMBtu, adjusted by market differentials by field. The net price per barrel of NGLs was $23.63, which was based on historical differentials to WTI as NGLs do not have any single comparable reference index price. Using these prices, at September 30, 2024 the cost center ceiling was higher than the capitalized costs of oil and natural gas properties and, as a result, no write-down was applicable.
At September 30, 2023, the ceiling test value of the Company’s reserves was calculated based on the first-day-of the month average for the 12-months ended September 30, 2023 of the WTI crude oil spot price of $78.53 per barrel and Henry Hub natural gas spot price of $3.43 per MMBtu, adjusted by market differentials by field. The net price per barrel of NGLs was $31.76, which was based on historical prices received as NGLs do not have any single comparable reference index price. Using these prices, at September 30, 2023 the cost center ceiling was higher than the capitalized costs of oil and natural gas properties and, as a result, no write-down was applicable.
Note 5. Senior Secured Credit Facility
On April 11, 2016, the Company entered into a senior secured reserve-based credit facility, as amended, (the “Senior Secured Credit Facility”) with MidFirst Bank in an amount up to $50.0 million with a current borrowing base of $50.0 million. On May 5, 2023, the Company entered into the Tenth Amendment to the Senior Secured Credit Facility extending the maturity to April 9, 2026. The Tenth Amendment also replaced the London Interbank Offered Rate ("LIBOR") with the Secured Overnight Financing Rate (“SOFR”) plus a credit spread adjustment of 0.05% to effectively convert SOFR to a LIBOR equivalent and modifies the Margined Collateral Value, as defined in the Ninth Amendment to the Senior Secured Credit Facility, to $95.0 million. The borrowing base will be redetermined semiannually, with the lenders and the Company each having the right to one interim unscheduled redetermination between any two consecutive semi-annual redeterminations. The borrowing base takes into account the estimated value of the Company’s oil and natural gas properties, proved reserves, total indebtedness, and other relevant factors consistent with customary oil and natural gas lending criteria. The Senior Secured Credit Facility carries a commitment fee of 0.25% per annum on the undrawn portion of the borrowing base. Any borrowings under the Senior Secured Credit Facility will bear interest, at the Company’s option, at either SOFR plus 2.80%, subject to a minimum SOFR of 0.50%, or the Prime Rate, as defined under the Senior Secured Credit Facility, plus 1.00%.
The Company may elect, at its option, to prepay any borrowings outstanding under the Senior Secured Credit Facility without premium or penalty. Amounts outstanding under the Senior Secured Credit Facility are guaranteed by the Company’s direct and indirect subsidiaries and secured by a security interest in substantially all of the properties of the Company and its subsidiaries. Borrowings under the Senior Secured Credit Facility may be used for the acquisition and development of oil and natural gas properties, investments in cash flow generating properties complimentary to the production of oil and natural gas, and for letters of credit or other general corporate purposes.
The Senior Secured Credit Facility contains certain events of default, including non-payment; breaches or representation and warranties; non-compliance with covenants; cross-defaults to material indebtedness; voluntary or involuntary bankruptcy; judgments and change in control. The Senior Secured Credit Facility also contains financial covenants including a requirement that the Company maintain, as of the last day of each fiscal quarter, (i) a maximum total leverage ratio of not more than 3.00 to 1.00, (ii) a current ratio of not less than 1.00 to 1.00, and (iii) a consolidated tangible net worth of not less than $40.0 million, each as defined in the Senior Secured Credit Facility. As of September 30, 2024, the Company had $39.5 million borrowings outstanding under its Senior Secured Credit Facility, resulting in $10.5 million of available borrowing capacity. For the three months ended September 30, 2024, the