Residential construction represents the most important single demand driver for us, driving around 80% of the demand for Gypsum Wallboard and about 30% of the demand for cement.
It was notable that President Biden said this month that he planned to make an historic investment in affordable housing by building and rehabilitating more than 2 million homes.
The National Association of Realtors said that there is a cumulative demand-supply gap of 6.8 million homes.
We have also restarted our share repurchase program and completed the issuance of 2.5% 10-year senior notes that will further strengthen Eagle's capital structure.
First quarter revenue was a record $476 million, an increase of 11% from the prior year.
First quarter earnings per share was $2.25.
That's a 3% decrease from the prior year.
However, the prior year included a $0.93 per share gain from the sale of our Northern California businesses.
Revenue in the sector increased 3% driven by the increase in cement sales prices.
The price increases range from $6 to $8 per ton and were effective in most markets in early April.
Operating earnings increased 3%, again reflecting higher cement prices, which were partially offset by higher maintenance spending in the first quarter of fiscal 2022.
The impact in the shift in timing and extent of the outages was approximately $10 million.
Revenue in our Light Materials sector increased 25%, reflecting higher wallboard sales volume and prices.
Operating earnings in the sector increased 51% to $67 million, reflecting higher net sales, prices, and volume, partially offset by higher input costs, namely recycled fiber costs and energy.
However, wallboard margins improved to 38% versus 32% in the prior year.
During the first quarter, operating cash flow increased 17% to $111 million, reflecting strong earnings and disciplined working capital management.
Capital spending declined $12 million.
And as Michael mentioned, we restarted our share repurchase program during the quarter and returned $62 million to shareholders during the quarter, which equated to approximately 426,000 shares.
And at June 30th, our net debt to cap ratio was 34% and our net debt to EBITDA leverage ratio was 1.2 times.
We ended the quarter with $307 million of cash on hand.
Subsequent to the quarter, we completed the refinancing of our capital structure, which included issuing $750 million of 10-year senior notes with an interest rate of 2.5%, extending our bank credit facility five years, paying off the bank term loan, and retiring our 2026 senior notes.

Summary:
First quarter revenue was a record $476 million, an increase of 11% from the prior year.
First quarter earnings per share was $2.25.