Costs and Expenses
Service Costs
Service costs increased 0.7% and 1.6% for the three and nine months ended September 30, 2019, respectively, primarily due to greater video programming and field operating costs, offset in part by lower HSD delivery costs. Programming costs were 1.0% and 1.2% higher for the three and nine months ended September 30, 2019, respectively, mainly due to contractual increases under agreements with certain local broadcast stations and cable networks, substantially offset by smaller video customer bases compared to the prior year periods. Field operating costs rose 4.0% and 4.4% for the three and nine months ended September 30, 2019, respectively, primarily due to greater plant installation, repair and maintenance costs. HSD delivery costs fell 10.5% and 10.3% for the three and nine months ended September 30, 2019 and 2018, respectively, principally due to lower maintenance service agreements and self-installation costs. Service costs as a percentage of revenues were 41.0% and 41.9% for the three months ended September 30, 2019 and 2018, respectively, and 41.2% and 41.9% for the nine months ended September 30, 2019 and 2018, respectively.
Selling, General and Administrative Expenses
Selling, general and administrative expenses decreased 1.0% and 0.7% for the three and nine months ended September 30, 2019, respectively, largely a result of lower marketing, office and bad debt expenses and, for the three months ended September 30, 2019, lower employee expenses. Marketing expenses declined 2.8% and 4.1% for the three and nine months ended September 30, 2019, respectively, mainly due to lower spending on print, mail and television advertising and third-party commission expenses. Office expenses fell 8.8% and 2.7% for the three and nine months ended September 30, 2019, respectively, primarily due to lower rent and equipment maintenance expenses. Bad debt expenses decreased 0.4% and 8.6% for the three and nine months ended September 30, 2019, respectively, substantially due to lower write-offs associated with customer accounts. Employee expenses decreased 4.3% for the three months ended September 30, 2019, primarily due to lower marketing and advertising staffing and compensation levels. Selling, general and administrative expenses as a percentage of revenues were 18.0% and 18.7% for the three months ended September 30, 2019 and 2018, respectively, and 17.4% and 18.1% for the nine months ended September 30, 2019 and 2018, respectively.
Management Fee Expense
Management fee expense grew 9.1% and 10.3% for the three and nine months ended September 30, 2019, respectively, reflecting higher fees charged by MCC. Management fee expense as a percentage of revenues was 2.4% and 2.3% for the three months ended September 30, 2019 and 2018, respectively, and 2.3% and 2.2% for the nine months ended September 30, 2019 and 2018, respectively.
Depreciation and Amortization
Depreciation and amortization was 1.6% higher for the three months ended September 30, 2019, respectively, mainly due to greater depreciation of investments in newer customer premise equipment, business customer support equipment and software and HSD bandwidth expansion, offset in part by older investments in customer premise equipment and network assets becoming fully depreciated.
Depreciation and amortization was 0.9% lower for the nine months ended September 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 10.1% and 11.2% for the three and nine months ended September 30, 2019, respectively, principally due to the increase in revenues.
Interest Expense, Net
Interest expense, net, increased 6.2% for the three months ended September 30, 2019, due to a higher average cost of debt, offset in part by lower average outstanding indebtedness.
Interest expense, net, fell 4.5% for the nine months ended September 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 gain on derivatives of $2.3 million for each of the three and nine months ended September 30, 2019, and a net loss on derivatives of $1.5 million and $0.9 million for the three and nine months ended September 30, 2018, respectively. See Notes 3 and 6 in our Notes to Consolidated Financial Statements.
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