Standard parts and service gross profit by 7.6% on 4.8% higher revenues from the prior year period. It should be noted that Toyota recalls accounted for only one percentage point of the revenue increase in the quarter. Global same-store revenues up 25% in the quarter and up 21.4% or $445 million in the first six months as compared with the first half of 2009.
Improved SG&A expense by 390 basis points sequentially to 77.3% of gross profit and achieved an operating margin of 3.2%. During the quarter we had some adjustments associated with dealership dispositions and severance charges for restructuring a too recently acquired UK dealerships. Excluding these adjustments, on a consolidated basis, SG&A as a percentage of gross profit improved 340 basis points to 78% from the prior quarter reflecting our ability to leverage our inter cost structure.
Our operating margins were 3% and earnings were up $0.75 per dilute share. Turning now to additional details on our new vehicle business. Our brand mix during the second quarter was comprised of 35% of unit sales from our Toyota/Scion/Lexus stores. We saw our Toyota unit sales increased 28% during the quarter, nearly doubling the national increase.
Our next largest brand was Nissan/Infiniti which accounted for 14% of unit sales and where we saw a 41% sales increase in the quarter. Next stuff was Honda/Acura at 12% and BMW now represents a 11.5% of our mix as we've continued to expand with this profitable brand. Rounding out our line-up is Ford at 9% with a 26% increase in unit sales. Mercedes-Benz at 6% and GM and Chrysler representing 4% and 3% of our unit sales respectively.In total Luxury and Import sales comprised 85% of our new vehicle unit sales. Our new vehicle inventories stood at 57 days' supply at quarter end. Looking at the used vehicle business, as I mentioned earlier our second quarter same-store used retail revenues were 32%, 24% more unit sales from the prior year period. Gross profit for retail unit increased slightly to $1,862. Our certified pre-owned business grew to represent 35% of our used vehicle retail sales in the quarter. Read the rest of this transcript for free on seekingalpha.com