On Wednesday, July 25, we announced the 31st consecutive increase in our quarterly distribution to $0.91 per unit, which is a 5% increase over the $0.865 per unit we declared for 2011 second quarter. Our distributable cash flow for the quarter ended June 30 was $34.5 million, up $13.1 million from the same period the previous year. Net income for the second quarter was $23.2 million versus $19 million for the same period in 2011. And the drivers of increased distributable cash flow and net income compared to the year-ago period are basically the same, the financial contribution of the assets that HEP acquired from HollyFrontier in November 2011, increased pipeline volumes and annual tariff increases.
As a reminder, the majority of HEP's revenues and, therefore, income and DCF are supported by minimum commitments from our major customers. These commitments as of June 30, 2012, totaled approximately $220 million per year or about $55 million per quarter and amount to 85% to 90% of our total revenue.
Operating expenses of approximately $17.9 million for the quarter were higher than 2011 second quarter amount of $14.4 million, primarily due to the inclusion of operating cost associated with our recently acquired assets serving HollyFrontier's El Dorado and Cheyenne Refineries and year-over-year increases in maintenance service, payroll and power costs. G&A expenses of $2.5 million for the quarter were higher than the previous year's second quarter number and a bit higher than our typical quarterly run rate, primarily due to transaction expenses related to the UNEV acquisition, which was announced June 28.
Now I'll cover a few details relating to shortfalls billed and deferred revenue recognized during the quarter. As a reminder, the payments we received from HollyFrontier and Alon for quarterly shortfall billings under their minimum commitments are included in distributable cash flow in the current accounting period but classified as deferred revenues, so not recorded as revenue on our income statement until such time as they can be recognized. Deferred revenue recognition results from shortfall billings in prior quarters for which clawback rights either are uses or expire.Read the rest of this transcript for free on seekingalpha.com