While our bottom line has grown by more than 20 fold.
And in fact, we were able to repay the entire $665 million purchase price of the Kosmos acquisition during the fiscal year, providing us with significant balance sheet firepower and financial flexibility going forward.
The paper mill expansion added 20% additional capacity, allowing Eagle to set a monthly production record for Wallboard paper in March.
Our safety culture has never been stronger with leading indicators of safety observations increasing by 114%, resulting in all of Eagle's businesses outperforming industry metrics yet again, and this gap is widening.
These two items drive approximately 80% of the demand for Gypsum Wallboard and about 30% of the demand for cement.
In fact, remarkably, state and local tax revenue grew by 1.8% in 2020.
This is largely because state and local personal income tax receipts rose 3.4% and state and local property tax receipts were up 3.9%.
This decision is important one in the context of our capital allocation priorities, which I might add, remain unchanged.
In fact, over the past three years we have invested just over $625 million in share repurchases and dividends.
This compares with nearly $700 million in growth acquisitions and $300 million inorganic improvement investments over that same time period.
Currently, over 7 million shares remain under the current repurchase authorization.
As such, I would like to announce that we are reinstating our quarterly cash dividend of $0.25 per share on our common stock.
This amount represents a 150% increase over the quarterly dividends that had been paid preceding the suspension.
Fiscal Year 2021 revenue was a record $1.6 billion, up 16% from the prior year.
The Kosmos Cement business contributed approximately $176 million of revenue during the year.
Revenue for the fourth quarter was up 12% to $343 million, reflecting a very strong end to our fiscal year.
Annual diluted earnings per share increased 46% to $7.99, reflecting the contribution from the Kosmos Cement business, improvement in the organic businesses, and a gain of approximately $0.98 per share on the sale of our Northern California businesses during the first quarter.
The fourth quarter earnings per share comparison was affected by the CARES Act, which generated a $37 million or $0.76 per share benefit in the prior year period.
The total financial impact from the winter storm was approximately $12 million during the fourth quarter.
Annual revenue in the sector increased 19%, driven primarily by the acquired Kosmos Cement business and higher cement sales volume and pricing.
Operating earnings increased 27%, again reflecting the acquired business and increased sales volume and pricing.
And margins improved 140 basis points to 23%.
The impact of this sector was approximately $6 million and mostly reflects higher energy costs.
The price increases range from $6 to $8 per ton and were effective in most markets in early April.
Annual revenue in our Light Materials sector increased 5%, reflecting improved Wallboard sales volumes and prices.
Annual operating earnings increased 2% to $193 million, reflecting higher net sales prices, partially offset by higher input prices, namely recycled fiber costs and the impact of starting up the paper mill after the expansion project.
During fiscal 2021, operating cash flow increased 61% to $643 million, reflecting earnings growth, disciplined working capital management and the receipt of our IRS refund.
Meanwhile, capital spending declined to $54 million.
in fiscal 2022, we expect capital spending to increase to a range of $95 million to $105 million as we restart several projects that were delayed because of the COVID-19 pandemic.
At March 31, 2021, our net debt to cap ratio was 36%, down from 60% at the end of the prior year, and our net debt to EBITDA leverage ratio was 1.3 times.
We ended the year with $264 million of cash on hand and total liquidity at the end of the quarter was approximately $1 billion, and we have no near-term debt maturities.

Summary:
This decision is important one in the context of our capital allocation priorities, which I might add, remain unchanged.
Revenue for the fourth quarter was up 12% to $343 million, reflecting a very strong end to our fiscal year.
Annual operating earnings increased 2% to $193 million, reflecting higher net sales prices, partially offset by higher input prices, namely recycled fiber costs and the impact of starting up the paper mill after the expansion project.
Meanwhile, capital spending declined to $54 million.