Natural gas transportation and trading firm
reported quarterly earnings of $68.2 million, or 65 cents per diluted share, compared to $102.9 million, or 98 cents per diluted share, during the same period last year.
OneOK's quarterly operating income was $218.7 million compared with $255.7 million last year. The decline reflected "a decrease in storage, marketing and transportation margins in the energy services segment," the company said in a press release.
Analysts surveyed by Thomson Reuters had expected 67 cents a share.
Shares of OneOK were recently moving 5% lower at $23.11 per share in after-hours trading.