We are pleased to have made meaningful progress on that front where we began the pandemic initially collecting approximately 40% of retail rents in April to collecting approximately 80% retail rents in the third, quarter a number that we expect to get better.
Additionally, we are pleased to report that 100% of our properties continue to remain open and accessible by our tenants in each of our markets and anecdotally the majority of our employees are voluntarily working in person at our properties or at our corporate offices each week while taking absolutely all prudent safety precautions, despite having the flexibility to work from home.
Of course, we are firmly against Prop 15 which would eliminate Prop 13 Taxpayer Protection.
And also, we are against Prop 21 which we believe is a flawed measure that would implement a significant amendment to existing rent control laws on the multifamily side, limiting landlords' rights and likely making the housing crisis in California even worse.
While the challenges we face today are complex, whether relating to the pandemic, racial, [Indecipherable] technology or legislative matters to name a few, we do believe that we are well positioned to navigate through and manage these challenges with, as Ernest mentioned our best-in-class assets, our 200 talented and dedicated employees and the strength of our balance sheet.
Last night we reported third quarter 2020 FFO of $0.44 per share and net income attributable to common stockholders of $0.08 per share for the third quarter.
Number one, our collections of monthly recurring billings continue to improve in Q3 over Q2 with total collections of approximately 89% in Q3 versus 80% in Q2.
We prepared for the worst-case scenario by modeling a $50 million quarterly burn rate at the beginning of this pandemic, not knowing what we were going into and in Q2, our actual burn rate was approximately $6 million.
In Q3, we ended up with a cash surplus of approximately $9 million and this is after the operating capital expenditures and the dividend.
We started Q3 with approximately $146 million of cash on the balance sheet and ended Q3 with approximately $155 million of cash on the balance sheet, primarily as a result of increased cash NOI, quarter-over-quarter due to our successful collection efforts outlined earlier by Adam.
Number three, we have additional liquidity of $250 million available on our line of credit, combined with an entire portfolio of unencumbered properties with the exception of our only mortgage which is on City Center Bellevue.
Number four, we believe we have embedded growth in cash flow in our office portfolio with approximately $30 million plus of growth in the office cash NOI between now and the end of 2022 as Steve will discuss later.
On October 15, Hawaii allowed tourists to come back to the island as they can demonstrate that they have had a negative COVID tests within the last 72 hours.
On the first day, there were approximately 10,000 tourists that landed in Hawaii, we expect that tourism inflow to continue to increase each week and to start benefiting our Hawaiian properties over the coming quarters.
Office properties excluding One Beach Street in San Francisco, which is under redevelopment were at 96% occupancy at the end of the third quarter, an increase of approximately 2% from the prior year.
More importantly, same-store cash NOI increased 13% in Q3 over the prior year, primarily from increases in base rent at La Jolla Commons, Torrey Reserve campus, City Center Bellevue and the Lloyd District portfolio.
Our retail properties continue to be significantly impacted by the pandemic, although the occupancy at our retail properties remain stable for the third quarter at 95% occupancy which was a decrease of approximately 3% from the prior year our retail collections have been challenging during the pandemic, as reflected in our negative same store cash NOI.
Our multifamily properties experienced a challenging quarter, as same-store cash NOI decreased approximately 5.4% due primarily from the increase in average occupancy -- or I'm sorry, due primarily from the decrease in average occupancy at Hassalo in Portland, offset by favorable master lease signed with a private university in San Diego area at the beginning of the quarter.
On a segment basis, occupancy was at 87.5% at the end of the third quarter, a decrease of approximately 3% from the prior year.
With these adjustments, in the last 10 days we have already seen leasing traffic increase from a weekly average of four to six tour's per week, to 10 to 12 tours per week.
We have captured a total of 11 new leases in just the last week.
The Embassy Suites' average occupancy for the third quarter of 2020 was 66% compared with the average occupancy in the second quarter of 2020 of 17%.
The average daily rate for the third quarter of 2020 was $209, which is approximately 40% of the prior year's ADR. Waikiki Beach Walk Retail suffered considerably with virtually no tourists on the island until recently.
We had COVID-19 adjustments amounting to 2% of what was billed in Q3 to our tenants and the balance of approximately 9% is the amount outstanding of what was billed in Q3.
This is compared to the second quarter collections of 81%, COVID-19 adjustments of 5% and Q2 amounts that were billed and still outstanding of 14%.
This is compared to a bad debt expense accounts receivable of approximately 14% of the outstanding uncollected amounts at the end of Q2 and bad debt expense of straight-line rent receivables of approximately 7% at the end of Q2.
However, from a big picture perspective, at the end of the third quarter, our total allowance for doubtful accounts, which reflects the cumulative bad debt expense charges recorded totals approximately 39% of our gross accounts receivable and approximately 3% of our straight-line rent receivables.
Let's talk about liquidity; as we look at our balance sheet and liquidity at the end of the third quarter, we had approximately $405 million in liquidity, comprised of $155 million of cash and cash equivalents and $250 million of availability on our line of credit, and only one of our properties is encumbered by mortgage.
Our leverage, which we measure in terms of net debt to EBITDA was 6.7 times on a quarterly, annualized basis.
On a trailing 12 month basis, our EBITDA would be approximately 6.0 times.
Our focus is to maintain our net debt-to-EBITDA at 5.5 times or below.
Our interest coverage and fixed charge coverage ratio ended the quarter at 3.6 times on a quarterly annualized basis and 3.9 times on a trailing 12 month basis.
As Bob said earlier, at the end of the third quarter, net of One Beach, which is under redevelopment our office portfolio stood at over 96% leased with just under 6% expiring through the end of 2021.
The weighted average base rent increase for our nine renewals completed during the quarter was 6.7% and it's also as Bob pointed out earlier, with leases already signed, we have locked in approximately $30 million of NOI growth in our office segment priced at approximately [Indecipherable] in 2020, $14 million in $2021 and $10 million in 2022.
We anticipate significant additional NOI growth in 2022 and 2023 through the redevelopment of leasing of 102,000 square feet at One Beach Street in San Francisco and 33,000 rentable square feet at 710 Oregon Square in the Lloyd submarket in Portland.
In addition, we have the ability to organically grow our office portfolio by up to an additional 768,000 square feet or 22% on sites we already own by building Tower 3 at La Jolla Commons, a 213,000 square foot tower that's currently into the city for permits and Blocks 90 and 103 at Oregon Square with two configuration options, one at 392,000 square feet and the other at 555,000 square feet, which we recently received the entitlements on from the Portland Design Review Commission.

Summary:
Last night we reported third quarter 2020 FFO of $0.44 per share and net income attributable to common stockholders of $0.08 per share for the third quarter.
Number one, our collections of monthly recurring billings continue to improve in Q3 over Q2 with total collections of approximately 89% in Q3 versus 80% in Q2.