Gross profit improved 12.4% to $134.9 million from $120.0 million in the prior year quarter. Adjusted gross profit* as a percent of total revenue was 30.6%, compared to 29.9% for the same period last year. Selling and administrative expense, as a percent of net revenue, was 18.5% compared to 19.6% in the prior year quarter. Higher volume provided better administrative expense leverage during the quarter and adjusted selling and administrative expense*, as a percent of net revenue, improved to 17.8% from 18.6% in the prior year quarter.
Net income was $27.8 million, or $0.94 per diluted share, compared to $19.2 million, or $0.64 per diluted share, in the prior year quarter. Adjusted net income* was $36.6 million, or $1.23 per diluted share, compared to $27.6 million, or $0.92 per diluted share in the prior year quarter. Adjusted net income adjusts for the impact of non-core items in both periods, including an addback for non-cash amortization expense related to acquisitions.
Adjusted EBITDA* was $67.1 million, a 20.7% increase from $55.6 million in the prior year quarter, largely due to higher sales, improved gross profit, and leveraging the Company’s administrative expenses. Adjusted EBITDA, as a percent of net revenue, was 15.2% compared to 13.9% in the prior year quarter.
Full Year 2020 Results Overview
For the year ended December 31, 2020, net revenue was $1,653.2 million, an increase of 9.4% from $1,511.6 million in 2019. On a same branch basis, net revenue improved 4.5% from the prior year. Residential same branch sales growth was 4.7% for the year, attributable to price gains and end-market and product mix, compared to an increase in total completions of 2.5%. Our large commercial construction end-market increased 15.3% for 2020, and increased 2.8% on a same branch basis.
Gross profit improved 17.3% to $510.0 million from $434.8 million in the prior year. Gross margin was 30.8% compared to 28.8% in the prior year. Adjusted gross profit* as a percent of total revenue was 30.9%, which adjusts for the Company’s share-based compensation expense and employee-related expenses associated with the COVID-19 pandemic, compared to 28.8% for the same period last year. Selling and administrative expense, as a percentage of net revenue, was 19.3% compared to 19.1% in the prior year. Adjusted selling and administrative expense*, as a percentage of net revenue was 18.5% compared to 18.4% in the prior year.
Net income was $97.2 million, or $3.27 per diluted share, compared to $68.2 million, or $2.28 per diluted share in the prior year. Adjusted net income* was $128.9 million, or $4.34 per diluted share, compared to $98.3 million, or $3.29 per diluted share in the prior year.
For the full year of 2020, adjusted EBITDA* was $245.6 million, a 24.8% increase from $196.8 million in the prior year. Adjusted EBITDA, as a percentage of net revenue, was 14.9%, compared to 13.0% in the prior year. Operating income was $161.9 million, a 33.6% increase from $121.2 million in the prior year. The incremental adjusted EBITDA margin* on same branch revenue growth was 54.2% (please refer to the Supplementary Tables at the end of this Press Release).
Net cash from operating activities was $180.8 million, an increase of 46.9% from $123.1 million in the prior year.
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