Good morning, and welcome to Spark Energy's second quarter 2021 earnings call. This call is also being broadcast via webcast, which can be located in the Investor Relations section of our website at sparkenergy.com. With us today from management is our CEO, Keith Maxwell; and our CFO, Jim Jones.
Please note that today's discussion may contain forward-looking statements, which are based on assumptions that we believe to be reasonable as of this date. Actual results may differ materially. We urge everyone to review the safe harbor statement in yesterday's earnings release as well as the risk factors in our SEC filings.
We undertake no obligation to update these statements as a result of future events, except as required by law. In addition, we will refer to both GAAP and non-GAAP financial measures.
For information regarding our non-GAAP financial measures and reconciliations to the most directly comparable GAAP measures, please refer to yesterday's earnings release. With that, I'll turn the call over to Keith Maxwell, our CEO..
One, make the world the greener and more sustainable plays; two, increase our adjusted EBITDA over time in order to provide additional benefit to our stakeholders and customers. Stay tuned for additional updates to come, and that concludes my prepared remarks. Now I'll turn the call over to Jim for his financial review.
Jim?.
Thank you, Keith. Good morning. In the quarter, we achieved $14.4 million in adjusted EBITDA compared to last year's second quarter of $24.7 million. Gross margin for the quarter was $26.4 million compared with $45 million last year.
In our retail electricity segment, gross margin was $21.7 million compared to $35.6 million in the second quarter last year. Volumes were lower due to a reduction in our customer base along with slightly decreased unit margins. However, our load is now concentrated in stronger margin residential customers, and we expect those margins to remain steady.
In our retail natural gas segment, gross margin was $4.8 million compared with $9.4 million in the second quarter last year. The decrease is attributable to lower volumes along with decreased unit margins as a result of commodity prices increasing.
G&A expenses of $10.7 million were lower compared to $21.3 million in the second quarter last year primarily due to a decrease in legal expenses, bad debt, employee cost and broker fees incurred in 2020. Total RCEs in the quarter were $347,000. Our attrition of 3.3% is down from 3.5% from the second quarter last year.
Our net income for the quarter was $24.8 million or income of $0.58 million per fully diluted share compared to net income of $26.8 million or $0.62 per fully diluted share in the second quarter of last year.
The decrease in net income is driven by reduced growth margin, partially offset by the noncash mark-to-market accounting associated with the hedges we put in place to lock in margins on our retail contracts, along with lower G&A expenses and depreciation and income taxes.
We had a mark-to-market gain this quarter of $19.7 million compared to a mark-to-market gain of $18 million a year ago. On June 15 and July 15, we paid the quarterly cash dividend on our Class A common stock and Series A preferred stock effectively.
On July 21, we announced second quarter dividend of $0.18125 per share on our common stock to be paid on September 15 and $0.54688 per share of preferred stock to be paid on October 15. That's all I have, Keith, back to you..
Thanks, Jim. We want to thank our employees and our suppliers for their hard work in producing a good quarter. And I want to thank Spark's customers for choosing us as their energy provider. We look forward to connecting with you soon. Thank you..
End of Q&A:.