We believe at least $23 billion of CARES Act funding under the Provider Relief Fund remains unallocated.
Our adjusted FFO of $0.81 per share and our funds available for distribution of $0.77 per share allow us to maintain our quarterly dividend of $0.67 per share.
The payout ratio is 83% of adjusted FFO and 87% of funds available for distribution.
As of January 31, based on 92% of our facilities reporting in, 95% of facilities have conducted or are scheduled within the next week for first-dose clinics.
The vaccination rate for residents is approximately 69%, and the vaccination rate for staff is approximately 36%.
For most facilities, the second-dose clinic, which occurs 21 days after the first dose, will also incorporate a new day of first doses for those residents or staff who are not available or who are not prepared for the vaccination during the first round clinic.
Our NAREIT FFO on a diluted basis was $173 million or $0.73 per share for the quarter as compared to $176 million or $0.77 per diluted share for the fourth quarter of 2019.
Revenue for the fourth quarter was approximately $264 million before adjusting for the nonrecurring writedown of straight-line receivables as well as other nonrecurring favorable revenue items.
Revenue for the quarter included approximately $12 million of noncash revenue.
We collected over 99% of our contractual rent, mortgage and interest payments for the fourth quarter and for January as well, excluding, of course, rental payments due from Daybreak, which is under a forbearance agreement and has not been making payments.
Our G&A expense was $10.4 million for the fourth quarter of 2020, in line with our estimated quarterly G&A expense of between $9.5 million and $10.5 million.
Interest expense for the quarter was $56 million, with a $4 million increase over the third quarter of 2020, primarily resulting from our October issuance of $700 million of 3.375% senior notes due February 2031.
As a result of the repayments, we terminated $225 million of LIBOR-based swaps and recorded approximately $12 million in early extinguishment of debt.
Our October bond issuance repaid $683 million of short-term LIBOR-based borrowings.
borrowings outstanding under our $1.25 billion credit facility and had approximately $163 million in cash and cash equivalents.
In March 2020, we entered into $400 million of 10-year interest rate swaps at an average swap rate of approximately 0.87%.
In the fourth quarter, we issued 4.2 million shares of common stock through our ATM program, generating $151 million in net cash proceeds.
At December 31, approximately 95% of our $5.2 billion in debt was fixed and our funded debt to adjusted annualized EBITDA was five times.
Our fixed charge coverage ratio was 4.3 times.
When adjusting to include a full quarter of contractual revenue for new investments completed during the quarter as well as eliminating revenue related to assets sold in the quarter, our pro forma leverage would be roughly 4.99 times.
As of December 31, 2020, Omega had an operating asset portfolio of 949 facilities with over 95,000 operating beds.
These facilities were spread across 69 third-party operators and located within 39 states and the United Kingdom.
Trailing 12-month operator EBITDARM and EBITDAR coverage for our core portfolio increased during the third quarter of 2020 to 1.87 times and 1.51 times, respectively, versus 1.84 times and 1.48 times, respectively, for the trailing 12-month period ended June 30, 2020.
During the third quarter, our operators cumulatively recorded approximately $102 million in federal stimulus funds as compared to approximately $175 million recorded during the second quarter.
Trailing 12-month operator EBITDARM and EBITDAR coverage would have decreased during the third quarter of 2020 to 1.53 times and 1.18 times, respectively, as compared to 1.61 times and 1.26 times, respectively, for the second quarter when excluding the benefit of any federal stimulus funds.
EBITDAR coverage for the stand-alone quarter ended September 30, 2020 for our core portfolio was 1.44 times, including federal stimulus funds, and 0.97 times excluding the $102 million of federal stimulus funds versus 1.87 times and 1.05 times with and without the $175 million in federal stimulus funds, respectively, for the second quarter.
Cumulative occupancy percentage for our core portfolio were at a pre-COVID rate of 84% in January of 2020, flattened out to around 75% throughout the fall months and subsequently dropped to 72.9% in December of 2020.
Based upon what Omega has received in terms of occupancy reporting for January to date, occupancy has continued to decline slightly, averaging approximately 72.1%.
Per patient day operating expenses for our core portfolio increased approximately $40 from pre-COVID levels in January 2020 to November 2020; the latest stats available.
On November 1, 2020, Omega completed a $78 million purchase lease transaction for 7 skilled nursing facilities in Virginia.
The facilities were added to an existing operator's master lease for an initial cash yield of 9.5% with 2% annual escalators.
New investments for the year ended December 31, 2020 totaled approximately $260 million including $113 million in capital expenditures.
As mentioned by Taylor, on January 20, 2021, Omega closed on the purchase of 24 senior housing facilities from Healthpeak for $510 million.
The portfolio primarily consists of assisted living, independent living and memory care facilities with a total of 2,552 units located across 11 states.
The facilities will generate approximately $43.5 million in contractual 2021 cash rent with annual escalators of 2.4%.
During the fourth quarter of 2020, Omega divested 16 facilities for total proceeds of $64 million.
For the year ended December 31, 2020, Omega strategically divested a total of 35 facilities for $181 million.
Since our last earnings call, the $175 billion Provider Relief Fund was increased by $3 billion as a result of the $900 billion stimulus package signed in December 2020.
Of that fund, approximately $23 billion remains unallocated.
In terms of previously allocated funds still in the process of being paid out, as previously mentioned, on July 22, a Medicare-certified nursing home targeted infection control fund of $5 billion was announced.
$2.5 billion was paid out in August and an additional $2 billion was set up as a quality incentive payment program with payments based on a facility's ability to maintain a rate of infection below the county infection rate and a death rate below a national performance threshold for nursing home residents.
The September payout was made in October at $330 million, with the October payout being made in December at $530 million and the November payout just starting to go out last week.
With respect to the Phase 2 general distribution announced in September, due to the fact that HHS hadn't previously tracked assisted living facilities, a lengthy tax identification process delayed the payout for many assisted living providers to December and early January.
This allocation was an application process for up to 2% of 2019 patient revenues from Medicaid, children's health insurance program and assisted living providers.
The $20 billion Phase 3 general distribution announced in October was increased to $24.5 billion once all applications were received and reviewed.
$10 billion was paid out in December with the remainder expected to be paid out within the coming weeks.
Payouts were based on the change in net operating income related to patient care for the first half of 2020 as compared to the first half of 2019, with a stated payout of 88%.
The final project cost is expected to be approximately $310 million.
By example, our Maplewood portfolio, which is concentrated in the early affected Metro New York and Boston markets, saw meaningful census erosion early in the pandemic, with second quarter census hitting a low point of 80.4% in early June.
That said, their portfolio occupancy had returned to 84.5% at the end of August and increased further to 85.6% in the month of November.
Including the land and CIP at the end of the fourth quarter, Omega's senior housing portfolio totaled $1.6 billion of investment on our balance sheet.
and U.K. As expected, this portfolio on a stand-alone basis had its trailing 12-month EBITDAR lease coverage fall four basis points to 1.12 times in the third quarter of 2020.
We invested $19.4 million in the fourth quarter in new construction and strategic reinvestment.
$12.8 million of this investment is predominantly related to our active construction projects.
The remaining $6.6 million of this investment was related to our ongoing portfolio capex reinvestment program.

Summary:
Our adjusted FFO of $0.81 per share and our funds available for distribution of $0.77 per share allow us to maintain our quarterly dividend of $0.67 per share.
Our NAREIT FFO on a diluted basis was $173 million or $0.73 per share for the quarter as compared to $176 million or $0.77 per diluted share for the fourth quarter of 2019.