Our results in the fourth quarter demonstrated Ventas' resilience with normalized FFO reported at $0.83 a share and $0.74 ex much appreciated funding from HHS to our senior living communities that have been affected by COVID-19.
At Ventas, we're proud that 100% of our U.S. SHOP, AL, and memory care communities have already received the vaccine and nearly 90% of them will complete their second dose by the end of this month.
In our SHOP communities, it is wonderful to know that about 30,000 vulnerable residents have already been vaccinated and are one step closer to feeling safe, seeing loved ones, and enjoying a richer life.
Our $280 million life sciences project known as One uCity in this rising research sub-market of Philadelphia, which is book ended by tenant Drexel is attracting significant leasing interest.
In addition to the nearly $1 billion ground-up development projects already under way, our university based development pipeline continues to hold about another $1 billion in active potential projects with both new and existing university relationships.
In particular with Wexford, we are in the design development phase of a nearly $0.5 billion project with a major research university on the West Coast that is substantially pre-leased.
We've had five projects under way with investment also totaling nearly $0.5 billion and two of the projects were delivered in the fourth quarter.
We are pleased to report that the two open communities have leased up quickly and occupancy is already nearly 80%.
Both Justin and Pete have been working with our deal team to target about $1 billion of disposition during the year to optimize our portfolio.
Finally, our institutional investment capital management platform continues to grow and succeed with well over $3 billion in assets under management.
Through this program, applicable to sequential same-store SHOP assets, our communities have received $34 million in the fourth quarter and $13 million to date in the first quarter, which has been applied as a contra expense to offset COVID-19 related expenses incurred.
Although the fourth quarter was a challenging quarter, we are pleased our occupancy hung in there with a 90 basis point decline.
Looking ahead to the remainder of the first quarter, for the forecast Q1 sequential same-store SHOP portfolio, we expect cash NOI to decline from the fourth quarter to the first quarter excluding HHS grants of $34 million and $13 million to date in each respective period.
This NOI deterioration is driven by 250 basis point to 325 basis point expected occupancy decline partially offset by modest rate increase.
And while we are seeing continued high levels of COVID related costs, these are partially mitigated by $13 million of Phase 3 HHS grant money received to date in the first quarter.
In the most recent week, we are averaging nine cases per day, which is the lowest since October and down from 92 cases per day at the peak in January.
As Debbie mentioned, 100% of our assisted living and memory care communities have hosted their first vaccine clinic.
I'll note that 95% of our communities are already open to move-ins, which is near pandemic high.
Currently, 80% of our communities are operating in Segment 3.
This is up from 64% a month ago.
Segment 3 is the least restrictive operating environment.
Our trailing 12 month cash flow coverage for senior housing is 1.3 times respectively.
In 2020, construction starts nationally were down 50% year-over-year and deliveries were at their lowest levels since 2013.
Our SHOP markets witnessed particularly favorable supply trends with starts down 66% versus the prior year and deliveries down over 40%.
Fewer starts today combined with a compelling aging demographic trends where the 80-plus population is expected to grow nearly 15% between now and 2024, which is 5 times faster than the broader population, will provide a potent tailwind over the next few years.
Together, these segments represent 47% of Ventas' NOI.
In fact, for the full year 2020, these segments combined to generate same-store cash NOI growth of 3%.
The office portfolio continues to provide steady growth, delivering $128 million of same-store cash NOI in the fourth quarter.
This represents a 1.5% sequential growth led by our R&I portfolio which generated 3.6% same-store cash NOI growth.
Moreover, full year office same-store cash NOI grew 3.3% versus 2019, near the midpoint of original 2020 office guidance of 3% to 4% despite the impacts of COVID-19.
Normalizing for a paid parking shortfall and increased cleaning costs due to COVID, same-store cash NOI grew 4.5%, surpassing our pre-COVID guidance range.
In terms of rent receipts, office tenants paid an industry-leading 99.2% of contractual rents in the fourth quarter.
For the entire period from April through December, tenants paid 99.4% of contractual rent.
Continuing the trend, we have collected 98% of January contractual rents, on track to meet or exceed the fourth quarter collection rate.
In our medical office portfolio, nearly 85% of our NOI comes from investment grade rated tenants and HCA.
In our R&I portfolio, 76% of our revenues come directly from investment grade rated organizations and publicly traded companies.
Medical office had a record level of retention of 88% for the fourth quarter and 87% for the trailing 12 months.
Driven by this retention, total office leasing was 700,000 square feet for the quarter and 3.4 million square feet for the full year of 2020.
This includes 540,000 square feet of new leasing.
As an example, paid parking receipts during the second quarter of 2020 were only 46% of normal.
During the fourth quarter, however, paid parking recovered to 71% of normal.
In the fourth quarter, we closed our acquisition of the three-asset, 800,000 square foot Trophy Life Sciences Portfolio in San Francisco.
Since last quarter's announcement, we have renewed a large tenant and signed two new leases, bringing the building to a 100% leased, a clear demonstration of the attractiveness of these buildings to the marketplace.
We also opened our $80 million R&I development on the campus of Arizona State located within the Phoenix Biomedical Campus, a 30-acre innovation district established by the City of Phoenix in the heart of downtown.
The building is over 50% pre-leased and is ahead of pro forma.
We have received 100% of fourth quarter rents as well as 100% of January and 100% of February rents.
Acute care hospitals trailing 12-month coverage was a strong 3.3 [Phonetic] in the third quarter, a 20 basis point sequential improvement driven by a rebound in elective surgical procedures, prudent expense management as well as government funding.
We invested approximately $30 million at a near 8% stabilized yield.
IRF and LTAC coverage improved 10 basis points to 1.6 times in the third quarter buoyed by strong business results and government funding.
Ventas reported fourth quarter net income attributable to common stockholders of $0.29 per share and normalized funds from operations of $0.83 per share or $0.74 excluding the $0.09 in HHS grants received in SHOP in Q4.
Other sequential fourth quarter drivers to highlight include $0.04 of income recorded in our unconsolidated entities offset by a $0.05 Q4 sequential decline in NOI principally in SHOP.
The key components of our Q1 guidance are as follows: net income attributable to common stockholders is estimated to range between minus $0.07 and minus $0.01 per fully diluted share; normalized FFO is forecast to range from $0.66 to $0.71 per share.
The midpoint of our FFO guidance $0.68 per share represents $0.15 sequential decline from the fourth quarter.
This change can be largely explained by $0.09 reduction in HHS grant income and income from unconsolidated entities.
The balance is driven by a $0.05 reduction in organic SHOP NOI performance.
A few of the key SHOP Q1 assumptions include Q1 2021 average occupancy ranging from 250 basis points to 325 basis points lower versus the fourth quarter average, sequential growth in RevPOR as a result of the annual in-place rent increases implemented at the start of 2021, and continued elevated levels of operating expenses driven by COVID labor and testing.
We finished 2020 with full year net debt-to-EBITDA of 6.1 times, maintained a strong maturity profile with duration exceeding six years, held total debt to gross asset value at 37%, reduced our net debt at year-end by over $500 million year-over-year, and retained robust liquidity exceeding $3 billion.
In 2020, we also took advantage of the strong bid for healthcare real estate and realized over $1 billion in asset sales at a blended 5.3% cash yield.
In 2021, we're targeting an additional $1 billion in asset sales across our verticals in the second half of the year.
In January 2021, we closed on a new four-year $2.75 billion unsecured credit facility.
We had great demand from 24 new and incumbent financial institutions and we're able to realize better pricing.
And finally, in March 2021, Ventas will use cash on hand from recent dispositions to reduce our near-term maturities by fully repaying $400 million of our 3.1% Senior Notes due January 2023.

Summary:
Our results in the fourth quarter demonstrated Ventas' resilience with normalized FFO reported at $0.83 a share and $0.74 ex much appreciated funding from HHS to our senior living communities that have been affected by COVID-19.
Ventas reported fourth quarter net income attributable to common stockholders of $0.29 per share and normalized funds from operations of $0.83 per share or $0.74 excluding the $0.09 in HHS grants received in SHOP in Q4.
The key components of our Q1 guidance are as follows: net income attributable to common stockholders is estimated to range between minus $0.07 and minus $0.01 per fully diluted share; normalized FFO is forecast to range from $0.66 to $0.71 per share.