Item 7A. Quantitative and Qualitative Disclosures About Market Risk

We maintain a mix of fixed-rate and variable-rate debt and we are exposed to the market risk of adverse changes in interest rates. In order to manage the cost and volatility relating to the interest cost of our outstanding debt, we enter into various interest rate risk management derivative transactions in accordance with our policy.

We monitor our exposure to the risk of adverse changes in interest rates through the use of techniques that include market valuation and sensitivity analyses. We do not engage in any speculative or leveraged derivative transactions.

Our interest rate derivative financial instruments, which may include swaps, rate locks, caps and collars, represent an integral part of our interest rate risk management program. Our interest rate derivative financial instruments reduced the portion of our total consolidated debt at fixed rates as of December 31, 2018 to 81.5% from 82.8%.

The effect of our interest rate derivative financial instruments was to decrease our consolidated interest expense by $6 million, $23 million and $36 million, in 2018, 2017 and 2016, respectively. The effect of NBCUniversal’s interest rate derivative financial instruments was not material to NBCUniversal’s consolidated financial statements for any period presented. Interest rate derivative financial instruments may have a significant effect on our consolidated interest expense in the future.

The table below summarizes as of December 31, 2018 by contractual year of maturity the principal amount of our debt, notional amount of our interest rate instruments, effective rates, and fair values subject to interest rate risk maintained by us.

The average interest rates on our debt in the table above reflect the effects of our derivative financial instruments. We estimate interest rates on variable rate debt and swaps using the relevant average implied forward rates through the year of maturity based on the yield curve in effect on December 31, 2018, plus the applicable borrowing margin. The notional amount of each interest rate derivative financial instrument is used to calculate the interest to be paid or received. The notional amounts do not represent our exposure to credit loss. The estimated fair value approximates the amount of payments to be made or proceeds to be received to settle the outstanding contracts, including accrued interest.

See Note 1 to each of Comcast’s and NBCUniversal’s consolidated financial statements for additional information on our accounting policies for derivative financial instruments.

We have significant operations in a number of countries outside the United States through Sky and NBCUniversal, and certain of our operations are conducted in foreign currencies. The value of these currencies fluctuates relative to the U.S. dollar. These changes could adversely affect the U.S. dollar equivalent value of our non-U.S. dollar revenue and operating costs and expenses, which could negatively affect our business, financial condition and results of operations in a given period or in specific territories.

As part of our overall strategy to manage the level of exposure to the risk of foreign exchange rate fluctuations, we enter into derivative financial instruments related to a significant portion of our foreign currency exposure for transactions denominated in other than the functional currency. We enter into foreign currency forward contracts that change in value as currency exchange rates fluctuate to protect the functional currency equivalent value of non-functional currency denominated assets, liabilities, commitments, and forecasted non-functional currency revenue and expenses. In accordance with our policy, we hedge forecasted foreign currency transactions for periods generally not to exceed 18 months. In certain circumstances, we enter into foreign exchange contracts with initial maturities in excess of 18 months. As of December 31, 2018 and 2017, we had foreign exchange contracts on transactions other than debt with a total notional value of $5.8 billion and $1.3 billion, respectively, including contracts at NBCUniversal of $1.2 billion and $1.3 billion, respectively. As of December 31, 2018 and 2017, the aggregate estimated fair value of these foreign exchange contracts was not material.

We use cross-currency swaps for foreign currency denominated debt obligations when those obligations are denominated in a currency other than the functional currency. Cross-currency swaps effectively convert foreign currency denominated debt to debt denominated in the functional currency in order to hedge the risk that the cash flows related to annual interest payments and the payment of principal at maturity may be adversely affected by fluctuations in currency exchange rates. The gains and losses on these cross-currency swaps generally offset changes in the underlying value of the related exposures. As of December 31, 2018 and 2017, we had cross-currency swaps on $5.3 billion and $0.8 billion notional amount of our foreign currency denominated

debt, respectively. As of December 31, 2018 and 2017, the aggregate fair value of these cross-currency swaps was a net liability of $23 million and $80 million, respectively.

We are also exposed to foreign currency exchange risk on the consolidation of our foreign operations. Beginning in 2018, we use foreign currency denominated debt and cross-currency swaps to hedge our net investments in certain of these subsidiaries. As of December 31, 2018, we had $15.6 billion notional amount of foreign currency denominated debt and cross-currency swaps designated as net investment hedges of our foreign subsidiaries.

We have analyzed our foreign currency exposure related to our foreign operations as of December 31, 2018, including our hedging contracts, to identify assets and liabilities denominated in a currency other than their functional currency. For those assets and liabilities, we then evaluated the effect of a hypothetical 10% shift in currency exchange rates, inclusive of the effects of derivatives. The results of our analysis indicate that such a shift in exchange rates would not have a material impact on our 2018 net income attributable to Comcast Corporation.

We manage the credit risks associated with our derivative financial instruments through diversification and the evaluation and monitoring of the creditworthiness of counterparties. Although we may be exposed to losses in the event of nonperformance by counterparties, we do not expect such losses, if any, to be significant. We have agreements with certain counterparties that include collateral provisions. These provisions require a party with an aggregate unrealized loss position in excess of certain thresholds to post cash collateral for the amount in excess of the threshold. The threshold levels in our collateral agreements are based on our and the counterparty’s credit ratings. As of December 31, 2018 and 2017, we were not required to post collateral under the terms of these agreements, nor did we hold any collateral under the terms of these agreements.