Management’s Discussion and Analysis of Financial Condition and Results of Operations - (continued)
(Amounts in Millions, Except Per Share Amounts)
Net cash provided by operating activities during 2014 was $669.5, which was an improvement of $76.6 as compared to 2013, primarily as a result of an increase in net income, offset by an increase in working capital usage of $121.5. Our net working capital usage in 2014 was impacted by our media businesses.
The timing of media buying on behalf of our clients affects our working capital and operating cash flow. In most of our businesses, our agencies enter into commitments to pay production and media costs on behalf of clients. To the extent possible, we pay production and media charges after we have received funds from our clients. The amounts involved substantially exceed our revenues and primarily affect the level of accounts receivable, expenditures billable to clients, accounts payable and accrued liabilities. Our assets include both cash received and accounts receivable from clients for these pass-through arrangements, while our liabilities include amounts owed on behalf of clients to media and production suppliers.
Our accrued liabilities are also affected by the timing of certain other payments. For example, while annual cash incentive awards are accrued throughout the year, they are generally paid during the first quarter of the subsequent year.
Net cash used in investing activities during 2015 primarily related to payments for capital expenditures of $161.1, largely attributable to purchases of leasehold improvements and computer hardware.
Net cash used in investing activities during 2014 primarily related to payments for capital expenditures and acquisitions. Capital expenditures of $148.7 related primarily to computer hardware and software and leasehold improvements. We made payments of $67.8 related to acquisitions completed during 2014, net of cash acquired.
Net cash used in financing activities during 2015 primarily related to the repurchase of our common stock and payment of dividends. We repurchased 13.6 shares of our common stock for an aggregate cost of $285.2, including fees, and made dividend payments of $195.5 on our common stock.
Net cash used in financing activities during 2014 primarily related to the purchase of long-term debt, the repurchase of our common stock and payment of dividends. We redeemed all $350.0 in aggregate principal amount of our 6.25% Notes, repurchased 14.9 shares of our common stock for an aggregate cost of $275.1, including fees, and made dividend payments of $159.0 on our common stock. This was offset by the issuance of $500.0 in aggregate principal amount of our 4.20% Notes.
Foreign Exchange Rate Changes
The effect of foreign exchange rate changes on cash and cash equivalents included in the Consolidated Statements of Cash Flows resulted in a decrease of $156.1 in 2015. The decrease was primarily a result of the U.S. Dollar being stronger than several foreign currencies, including the Australian Dollar, Brazilian Real, Canadian Dollar, Euro and South African Rand as of December 31, 2015 compared to December 31, 2014.
The effect of foreign exchange rate changes on cash and cash equivalents included in the Consolidated Statements of Cash Flows resulted in a decrease of $101.0 in 2014. The decrease was primarily a result of the U.S. Dollar being stronger than several foreign currencies, including the Australian Dollar, Brazilian Real, Canadian Dollar and Euro as of December 31, 2014 compared to December 31, 2013.
Balance Sheet Data
Cash, cash equivalents and marketable securities
Current portion of long-term debt
We expect our cash flow from operations, cash and cash equivalents to be sufficient to meet our anticipated operating requirements at a minimum for the next twelve months. We also have a committed corporate credit facility as well as uncommitted facilities available to support our operating needs. We continue to maintain a disciplined approach to managing liquidity, with flexibility over significant uses of cash, including our capital expenditures, cash used for new acquisitions, our common stock repurchase program and our common stock dividends.