We continue to enhance our product mix with a record contribution from our sub-1 megawatt plus interconnection category.
Our full-spectrum product offering continues to blossom with record sub-1 megawatt bookings in the second quarter and regional highs in both EMEA and APAC.
Together, with interconnection, the sub-1 megawatt category comprised nearly half of our total bookings, demonstrating customers' enthusiastic adoption of PlatformDIGITAL to help accomplish their digital transformation initiatives.
I'll discuss our sustainable growth initiatives on Page 3.
During the second quarter, we published our third annual ESG report, detailing our 2020 sustainability initiatives, including the utilization of renewable energy for 100% of our energy needs across our entire portfolio in Europe as well as our U.S. colocation portfolio and reaching 50% of our global needs.
We also recently underscored our commitment to transparency and accountability on our diversity, equity and inclusion journey with the publication of our EEO-1 report.
Let's turn to our investment activity on Page 4.
We are continuing to invest in our global platform with 39 projects underway around the world as of June 30, totaling nearly 300 megawatts of incremental capacity, most of which is scheduled for delivery over the next 12 months.
We are investing most heavily in EMEA with 19 projects totaling over 150 megawatts of capacity under construction.
Demand remains strong across these metros, and each continues to attract service providers as well as enterprise customers from around the world, many of which contributed to a truly standout performance by the region during the second quarter in the up-to-1 megawatt category.
We have 30 megawatts under construction in Portland or, more specifically, Hillsboro, that are now fully pre-leased, while our Toronto connected campus continues to gain momentum as the premier Canadian hub for global cloud service providers and enterprise customers.
Demand for this scarce capacity is robust, and we have another 18 megawatts largely presold and scheduled to open this quarter.
Let's turn to the macro environment on Page 5.
The first of these trends is the growing importance of data gravity for Global 2000 enterprises.
Market Intelligence firm, Gartner, recently conducted its 6th annual survey of chief data officers, and less than 35% of these executives reported their business have achieved their data sharing objectives, including data exchange with external data sources that drive revenue-generating business outcomes.
Recent research indicates that enterprise workflows utilize an average of 400 unique data sources, while exchanging data with 27 external cloud products.
Let's turn to our leasing activity on Page 7.
We signed total bookings of $113 million in the second quarter, including a $13 million contribution from interconnection.
Network and enterprise-oriented deals of 1 megawatt or less reached an all-time high of $41 million, demonstrating our consistent momentum and the growing success of PlatformDIGITAL as we continue to capture a greater share of enterprise demand.
We landed 109 new logos during the second quarter, with a strong showings across all regions, again, demonstrating the power of our global platform.
The geographic and product mix of our new activity was quite healthy, with APAC and EMEA, each contributing approximately 20%, the Americas representing nearly 50%, and interconnection responsible for a little over 10%.
A Global 2000 enterprise data platform is adopting PlatformDIGITAL in Amsterdam, Dublin and Frankfurt to orchestrate workloads across hundreds of ecosystem applications, delivering improved performance, security, cost savings, and simplicity.
Turning to our backlog on Page 9.
The current backlog of leases signed but not yet commenced ticked down from $307 million to $303 million as commencement slightly eclipsed space and power leases signed during the quarter.
Moving on to renewal leasing activity on Page 10.
We signed $178 million of renewals during the second quarter in addition to new leases signed.
The weighted average lease term on renewals signed during the second quarter was just under three years, again, reflecting a greater mix of enterprise deals smaller than 1 megawatt.
We retained 77% of expiring leases, while cash releasing spreads on renewals were slightly positive, also reflective of the greater mix of sub-1 megawatt renewals in the total.
In terms of second quarter operating performance, overall portfolio occupancy ticked down by 60 basis points as we brought additional capacity online across six metros during the quarter.
Same capital cash NOI growth was negative 1.5% in the second quarter, largely driven by the churn in Ashburn at the beginning of the year.
Let's turn to our economic risk mitigation strategies on Page 11.
Given our strategy of matching the duration of our long-lived assets with long-term fixed-rate debt, a 100 basis-point move in benchmark rates would have roughly a 75 basis-point impact on full year FFO per share.
In terms of earnings growth, second quarter core FFO per share was flat year-over-year but down 8% from last quarter driven by $0.12 noncash deferred tax charge related to the higher corporate tax rate in the U.K., which came into effect during the second quarter.
As you could see from the bridge chart on Page 12, we expect our bottom line results to improve sequentially over the balance of the year as the deferred tax charge comes out of the quarterly run rate and the momentum in our underlying business continues to accelerate.
Last, but certainly not least, let's turn to the balance sheet on Page 13.
As you may recall, we closed on the sale of a portfolio of noncore assets in Europe for $680 million late in the first quarter, which impacted second quarter adjusted EBITDA to the tune of approximately $10 million.
Fixed charge coverage ticked down slightly, also reflecting the near-term impact from asset sales, but remains well above our target and close to an all-time high at 5.4x, reflecting the results of our proactive liability management.
In mid-May, we redeemed $200 million of preferred stock at 6.625%, which brought total preferred equity redemptions over the prior 12 months to $700 million at a weighted average coupon of just over 6.25%, effectively lowering leverage by 0.3 turns.
In mid-June, we issued 0.5 million shares under our ATM program, raising approximately $77 million.
In early July, we raised another $26 million with the sale of the balance of our Megaport stock.
We also took our first trip to the Swiss bond market in early July, raising approximately $595 million in a dual tranche offering of Swiss green bonds with a weighted average maturity of a little over six and a half years and a weighted average coupon of approximately 0.37%.
As you can see from the chart on Page 13, our weighted average debt maturity is nearly six and a half years, and our weighted average coupon is down to 2.2%.
dollar-denominated, reflecting the growth of our global platform and serving as a natural FX hedge for our investments outside the U.S. 90% of our debt is fixed rate to guard against a rising rate environment, and 98% of our debt is unsecured, providing the greatest flexibility for capital recycling.
Finally, as you can see from the left side of Page 13, we have a clear runway with nominal near-term debt maturities and no bar too tall in the out years.

Summary:
As you may recall, we closed on the sale of a portfolio of noncore assets in Europe for $680 million late in the first quarter, which impacted second quarter adjusted EBITDA to the tune of approximately $10 million.