Costs and Expenses
Service Costs
Service costs increased 1.9% and 2.0% for the three and six months ended June 30, 2019, respectively, primarily due to greater field operating, employee and video programming costs. Field operating costs rose 8.4% and 4.7% for the three and six months ended June 30, 2019, respectively, primarily due to greater plant repair and maintenance costs. Employee costs grew 7.0% and 7.3% for the three and six months ended June 30, 2019, respectively, principally due to greater field employee staffing and compensation levels. Programming costs were 0.2% and 1.2% higher for the three and six months ended June 30, 2019, respectively, mainly due to contractual increases under agreements with certain local broadcast stations and cable networks, offset in part by smaller video customer bases compared to the prior year periods. Service costs as a percentage of revenues were 41.3% and 42.0% for the three months ended June 30, 2019 and 2018, respectively, and 41.3% and 41.9% for the six months ended June 30, 2019 and 2018, respectively.
Selling, General and Administrative Expenses
Selling, general and administrative expenses decreased 0.8% and 0.6% for the three and six months ended June 30, 2019, respectively, largely a result of lower bad debt and marketing expenses and taxes and fees, mostly offset by greater employee expenses. Bad debt expenses fell 18.1% and 14.5% for the three and six months ended June 30, 2019, respectively, substantially due to lower write-offs associated with customer accounts. Marketing expenses declined 5.2% and 4.7% for the three and six months ended June 30, 2019, respectively, mainly due to lower spending on print, mail and television advertising and lower spending on the marketing of our business services. Taxes and fees decreased 6.2% and 4.1% for the three and six months ended June 30, 2019, respectively, mainly due to lower property taxes and franchise fees. Employee expenses grew 7.2% and 3.8% for the three and six months ended June 30, 2019, respectively, primarily due to greater customer service and advertising staffing and compensation levels. Selling, general and administrative expenses as a percentage of revenues were 17.1% and 17.9% for the three months ended June 30, 2019 and 2018, respectively, and 17.1% and 17.8% for the six months ended June 30, 2019 and 2018, respectively.
Management Fee Expense
Management fee expense grew 12.1% and 11.0% for the three and six months ended June 30, 2019, respectively, reflecting higher fees charged by MCC. Management fee expense as a percentage of revenues was 2.1% and 1.9% for the three months ended June 30, 2019 and 2018, respectively, and 2.2% and 2.1% for the six months ended June 30, 2019 and 2018, respectively.
Depreciation and Amortization
Depreciation and amortization was 1.1% and 2.2% lower for the three and six months ended June 30, 2019, respectively, mainly due to older investments in customer premise equipment and network assets becoming fully depreciated, offset in part by depreciation of investments in newer customer premise equipment, business customer support equipment and software and HSD bandwidth expansion.
Operating Income
Operating income rose 11.1% and 11.7% for the three and six months ended June 30, 2019, respectively, primarily due to the increase in revenues, offset in part by higher service costs.
Interest Expense, Net
Interest expense, net, increased 1.8% for the three months ended June 30, 2019, due to a higher average cost of debt, mostly offset by lower average outstanding indebtedness.
Interest expense, net, fell 9.1% for the six months ended June 30, 2019, due to lower average outstanding indebtedness, offset in part by a higher average cost of debt.
Gain on Derivatives, Net
As a result of the changes in themark-to-market valuations on our interest rate exchange agreements, we recorded a net loss on derivatives of $0.8 million for the three months ended June 30, 2018, and a net gain on derivatives of $0.7 million for the six months ended June 30, 2018. See Notes 3 and 6 in our Notes to Consolidated Financial Statements.
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