pre_text: 15. QUARTERLY FINANCIAL INFORMATION (UNAUDITED) During the quarter ended December 31, 2019, we purchased a group annuity contract to transfer the pension benefit obligations and annuity administration for a select group of retirees or their beneficiaries to an annuity provider. As a result of the transfer of the pension liability to the annuity provider and other lump sum payments to participants of the Pension Plans, we recognized a non-cash pension settlement charge of $6.7 million during the quarter ended December 31, 2019. In 2019, we recognized a gain on extinguishment of debt from the partial repurchase of our Senior Notes of $0.3 million, $1.1 million and $3.1 million during the quarters ended June 30, 2019, September 30, 2019, and December 31, 2019, respectively. As part of our integration efforts of FairPoint and continued cost saving initiatives, we incurred severance costs of $8.7 million during the quarter ended December 31, 2019.
table: Quarter Ended
table: 2019 March 31, June 30, September 30, December 31,
table: (In thousands, except per share amounts)
table: Net revenues $338,649 $333,532 $333,326 $331,035
table: Operating income $16,720 $14,300 $23,542 $26,719
table: Net income (loss) attributable to common stockholders $(7,265) $(7,387) $257 $(5,988)
table: Basic and diluted earnings (loss) per share $(0.11) $(0.10) $— $(0.08)
question: Analyse this data from a financial earnings document. What is the average Operating income for each quarter in 2019?