HOUSTON — Group 1 Automotive Inc. reported adjusted first-quarter 2013 net income of $29.2 million, a 26.5 percent increase from a year ago, and adjusted diluted earnings per common share of $1.16, a 19.6 percent year-over-year increase.

Total gross profit for the first quarter grew 15.4 percent on 18 percent higher revenues of $2 billion.

New-vehicle revenue increased 21.7 percent on 18.5 percent higher unit sales, as same-store new vehicle unit sales grew 5.8 percent. Used-vehicle retail revenue also increased 13.6 percent on 12 percent higher used retail unit sales.

Selling, general and administrative (SG&A) expenses as a percent of gross profit improved 110 basis points to 75.4 percent, with a same-store improvement of 130 basis points to 74.7 percent.

Operating margin expanded 10 basis points to 3.3 percent, with a same-store operating margin expansion of 20 basis points to 3.5 percent. Pretax income grew 25.4 percent to $46.8 million, while the consolidated effective tax rate was 37.7 percent.

Diluted earnings per common share increased 19.6 percent to $1.16 on 26.5 percent higher net income of $29.2 million, both record first-quarter results for the company.

As previously announced during the first quarter, Group 1 acquired four franchises in the United Kingdom and 22 franchises in Brazil with total estimated annual revenues of approximately $827 million. It also disposed of a franchise in California that generated trailing-12-month revenues of $35 million.

"I am pleased with Group 1's first-quarter operating results including significant revenue growth and solid expense leverage that delivered record first-quarter earnings," said Earl J. Hesterberg, Group 1's president and chief executive officer. "We also significantly expanded the scale of our U.K. business and entered the rapidly-growing Brazilian automotive market. This is an exciting time for our company — an unprecedented growth phase which should support strong returns for our shareholders over time."