Cement revenue, including Joint Venture and intersegment revenue, was up 3% to $270.3 million. Operating earnings were also up 3% to a record $62.5 million. These increases reflect improved Cement quarterly sales prices, partially offset by lower Cement sales volume. The average net Cement sales price for the quarter was up 7% to $116.34 per ton. Cement sales volume for the quarter was down 2% to 2.0 million tons, mainly because of heavy rainfall in Texas during the quarter.
Concrete and Aggregates revenue increased 2% to $44.8 million, reflecting improved Concrete and Aggregates prices, partially offset by lower Aggregates sales volume. First quarter operating earnings decreased 1% to $5.3 million, reflecting lower Aggregates sales volume partially offset by improved Concrete and Aggregates net sales prices.
Light Materials: Gypsum Wallboard and Paperboard
Revenue in the Light Materials sector, which includes Gypsum Wallboard and Paperboard, increased 25% to $191.3 million, reflecting higher Wallboard sales volume and prices. Gypsum Wallboard sales volume increased 8% to 763 million square feet (MMSF), while the average Gypsum Wallboard net sales price increased 21% to $176.79 per MSF.
Paperboard sales volume increased 9% to a record 84,000 tons. The average Paperboard net sales price in the quarter was $498.49 per ton, up 8%, consistent with the pricing provisions in our long-term sales agreements.
Operating earnings were $66.6 million in the sector, an increase of 51%, reflecting increased Wallboard sales volume and pricing.
Details of Financial Results
We conduct one of our cement plant operations through a 50/50 joint venture, Texas Lehigh Cement Company LP (the Joint Venture). We use the equity method of accounting for our 50% interest in the Joint Venture. For segment reporting purposes only, we proportionately consolidate our 50% share of the Joint Venture’s revenue and operating earnings, which is consistent with the way management organizes the segments within the Company for making operating decisions and assessing performance.
In addition, for segment reporting purposes, we report intersegment revenue as a part of a segment’s total revenue. Intersegment sales are eliminated on the income statement. Refer to Attachment 3 for a reconciliation of these amounts.
On September 18, 2020, the Company sold its Oil and Gas Proppants business to Smart Sand, Inc. The prior-year financial results of the Oil and Gas Proppants segment have been classified as Discontinued Operations on the Consolidated Statement of Earnings. The assets and liabilities of the Oil and Gas Proppants segment have been reflected on separate lines for Discontinued Operations on the Consolidated Balance Sheet.
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