Christopher Forsythe
Analyst · UBS
Thank you, Kevin, and good morning, everyone. Last night, we reported fiscal 2020 second quarter diluted earnings per share of $1.95 compared to $1.82 per diluted share in the prior year quarter. Year-to-date, diluted earnings per share were $3.42 compared with $3.21 per diluted share in the prior year period.
As Kevin mentioned in his opening remarks, mitigation efforts to slow the spread of COVID-19 began to impact our service territories during the last 2 weeks of March. Therefore, we did not experience a material impact from COVID-19 during the first 6 months of the fiscal year. Consolidated operating income during the 6 months ended March 31 rose over 9% to $584 million.
I will touch on a few of the highlights now. Rate increases in both our operating segments, driven by increased safety and reliability capital spending, totaled $83 million. Customer growth in our distribution segment contributed incremental $8.5 million as we continue to benefit from the strong population growth in several of our service areas, most notably in the DFW Metroplex. For the 12 months ended March 31, we experienced 1.5% net customer growth in our North Texas distribution business and 1.2% net customer growth across our 8-state footprint.
Consolidated O&M increased $12 million or 4.2% primarily driven by higher employee and information technology costs and pipeline and maintenance activities. The period-over-period increase also reflects well integrity work that incurred during our first fiscal quarter.
Slides 5 and 6 provide additional details of the period-over-period changes to operating income for each of our segments. Consolidated capital spending for the 6-month period grew 28% to $995 million, with 87% directed towards safety and reliability spending to modernize our system. Because of our designation as an essential service provider and the measures we have taken to protect our employees and contractors, we still believe our fiscal 2020 capital spending will range between $1.85 billion and $1.95 billion.
Our fiscal second quarter is the busiest regulatory filing period of our fiscal year. Year-to-date, we have implemented $58 million of annualized operating regulatory outcomes. And currently, we have about $215 million in progress. Of this amount, we currently anticipate to implement approximately $100 million in annualized regulatory outcomes by the end of the fiscal year. Slides 21 to 31 provide details for all of these filings. Slide 20 outlines our planned activities for the remainder of the fiscal year.
Maintaining the strength of our balance sheet and a strong liquidity position continues to be one of our primary financial objectives, and it has served us well during this uncertain time. During the second quarter, we filed a $4 billion shelf registration statement and we filed a new $1 billion ATM program.
Also in the second quarter, we executed new forward sales agreements for approximately 1.6 million shares with anticipated proceeds of $180 million as of March 31, we had about $419 million in cash available under equity forward arrangements. With this activity, we have priced all of our anticipated equity needs for fiscal 2020 and a portion of fiscal 2021.
Additionally, the strength of our balance sheet supports our Tier 1 commercial paper rating. As a result, we have been able to maintain reasonable access to the commercial paper markets. As of March 31, we had about $200 million in outstanding commercial paper. At the end of the second quarter, our equity capitalization was 58.2%, and we had approximately $2 billion of liquidity under our credit facilities and equity forward agreements.
Kevin mentioned in his opening remarks, we took action in April to increase our liquidity to approximately $2.9 billion. We accomplished this through the execution of a $200 million 2-year term loan and 3 new 364-day credit facilities totaling $700 million. The net proceeds from the term loan were used to repay all outstanding commercial paper backstopped by our primary $1.5 billion credit facility.
This facility is fully available and in place through September 2023. Additional details regarding our liquidity can found on Slide 10. We believe this liquidity position, the strength of our balance sheet and $3 billion available under our shelf registration statement gives us the financial flexibility to support our operations as we move forward.
Looking towards the second half of the fiscal year, we are certainly aware that the economies of the service areas we serve have been impacted by the COVID-19 pandemic, and recent economic data reflects rising unemployment in each of our states. However, based on what we know today, we still expect earnings per share in the range of $4.58 to $4.73.
We considered a number of factors in our evaluation. First, our winter heating season is complete. We typically earn approximately 70% of our distribution revenues during the first half of our fiscal year. In our distribution segment, although we are not fully decoupled, we believe there are factors that mitigate revenue risk for this segment. These factors are summarized on Slide 14.
Residential revenues comprise approximately 60% of the segment's revenues during the second half of the fiscal year and residential builds were at their lowest during this time. Additionally, we collect a significant portion of our revenues, excluding gas cost, through the base charge, which partially insulates us from volumetric risk. For most of our service territories, the base charge represents the largest portion of the customer's bill by the middle of our third fiscal quarter.
We typically experience a decline in volumes during April. However, given that April is a shoulder month, it is difficult for us to identify if changes in volumes are weather related or representative of underlying economic activity. Therefore, we have provided some sensitivity information by customer class on Slide 14.
Additionally, the rate design and various annual filing mechanisms in our distribution segment support our ability to recover our costs timely. Slide 15 summarizes various aspects of rate design by state. Most of these mechanisms are well understood by you. However, I wanted to highlight that since March 31, our regulators in Louisiana, Mississippi, Texas and Virginia had issued orders to defer COVID-19-related costs, including bad debt expense, into a regulatory asset for consideration for future recovery. These orders cover approximately 80% of our customers.
Finally, as Kevin mentioned in his opening remarks, for approximately 32% of our customers in Texas, including the City of Dallas, we have voluntarily delayed implementation of new rates that were scheduled to go into effect during our fiscal third quarter to at least September 1. These delayed implementations will not have a material impact to our fiscal 2020 financial performance due to the time of year if these rates would have been implemented.
In our pipeline and storage segment, revenues are earned primarily through demand fees. As you're aware, performance of the segment is predominantly driven by APT. Over 80% of APT's revenues are earned from delivery services to our North Texas distribution company and a few other LDCs under a straight, fixed, variable rate design. The remainder of APT's revenues relate to its 3-system business and other ancillary pipeline services. As a reminder, APT only keeps 25% of revenues earned from these activities under its rate design. And the COVID-19 regulatory asset order issued by the Texas Railroad Commission also applies to APT.
Finally, from an O&M perspective, we have deferred some discretionary spending to future periods as we remain focused on the health and safety of our employees. Slides 17 and 18 provide additional details around our guidance.
Thank you for your time this morning. I will now turn the call back over to Kevin for some closing remarks.