Oil and Natural Gas Expenditures Our drilling and completion costs increased in 2017 compared to 2016 primarily as a result of increased drilling and completion activity as well as higher service and supply costs. During 2017, our average operated rig count was 17 rigs compared to an average operated rig count of ten rigs in 2016 and we completed 401 operated wells in 2017 compared to 382 in 2016. Our acquisitions of proved and unproved properties were higher in 2016 compared to 2017 and 2015, primarily resulting from purchases of oil and natural gas interests previously sold to third parties in connection with five of our VPP transactions for approximately $387 million. Repurchase of Debt In 2017, we used $2.592 billion of cash to repurchase $2.389 billion principal amount of debt. In 2016, we used $2.734 billion of cash to repurchase $2.884 billion principal amount of debt. In 2015, we used $508 million of cash to repurchase $513 million principal amount of debt. Dividends We paid dividends of $183 million on our preferred stock during 2017, including $92 million of dividends in arrears that had been suspended throughout 2016. We did not pay dividends on our preferred stock in 2016 and paid $171 million of preferred stock dividends in 2015. We paid dividends of $118 million on our common stock in 2015. We eliminated common stock dividends in the 2015 third quarter and do not anticipate paying any common stock dividends in the foreseeable future.
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