The rig count fell to historic lows, and RPC's quarterly revenues fell to their lowest level since 2004.
For the second quarter of 2020, revenues decreased to $89.3 million compared to $358.5 million in the prior year.
Adjusted operating loss for the second quarter was $35.9 million compared to an operating income of $8.4 million in the second quarter of the prior year.
Adjusted EBITDA for the second quarter was negative $17.8 million compared to EBITDA of $51.2 million in the same period of the prior year.
For the second quarter of 2020, RPC reported a $0.10 adjusted loss per share compared to $0.03 diluted earnings per share in the prior year.
Cost of revenues during the second quarter was $80 million or 89.6% of revenues compared to $265.1 million or 73.9% of revenues during the second quarter of 2019.
Selling, general and administrative expenses decreased to $28.8 million in the second quarter compared to $43.3 million in the second quarter of the prior year.
Depreciation and amortization decreased to $19.6 million in the second quarter of 2020 compared to $42.9 million in the second quarter of prior year.
Our Technical Services segment revenues for the quarter decreased 76.2% compared to the same quarter in the prior year.
Operating loss in the second quarter was $34.1 million compared to a $6.9 million operating profit in the second quarter of the prior year.
Our Sports Services segment revenues for the quarter decreased 57.2% compared to the same quarter in the prior year.
Operating loss in the second quarter of 2020 was $1.9 million compared to a $4 million operating profit in the second quarter of the prior year.
On a sequential basis, RPC's second quarter revenues decreased 63.4% to $89.3 million from $243.8 million in the prior quarter.
Cost of revenues during the second quarter of 2020 decreased by $101.9 million or 56%, due to lower materials and supplies and fuel expenses caused by decreased activity and lower employment costs resulting primarily from headcount reductions.
As a percentage of revenues, cost of revenues increased significantly from 74.6% in the first quarter to 89.6% in the second quarter.
Selling, general and administrative expenses during the second quarter decreased 21.2% to $28.8 million from $36.5 million in the prior quarter.
RPC incurred an adjusted operating loss of $35.9 million during the second quarter compared to an adjusted operating loss of $13.2 million in the prior quarter.
RPC's adjusted EBITDA was negative $17.8 million in the second quarter compared to adjusted EBITDA of $25.8 million in the prior quarter.
Despite the rapid decline in activity, our decremental EBITDA margin was only 28% due to our cost reduction efforts.
Technical Services segment revenues decreased $147.2 million or 64.6% to $80.5 million in the second quarter.
RPC's Technical Services segment incurred a $34.1 million operating loss compared to an operating loss of $12.2 million in the prior quarter.
Our Support Services segment revenues decreased by $7.3 million or 45.5% to $8.8 million in the second quarter.
Operating loss was $1.8 million compared to $1.5 million operating profit in the prior quarter.
At the end of second quarter of 2020, RPC's pressure pumping capacity remained at approximately 728,000 hydraulic horsepower.
Second quarter 2020 capital expenditures were $14 million, and we currently estimate full year capital expenditures to be $50 million to $60 million.
In fact, our $145 million in cash at the end of the second quarter was the highest in decades.

Summary:
For the second quarter of 2020, RPC reported a $0.10 adjusted loss per share compared to $0.03 diluted earnings per share in the prior year.
On a sequential basis, RPC's second quarter revenues decreased 63.4% to $89.3 million from $243.8 million in the prior quarter.