Piper Jaffray analyst Gene Munster today “revealed that the latest domestic sales data from the NPD Group shows U.S. sales down 7 percent year over year through the first two months of the September quarter,” AppleInsider reports.

“But in both the March and June quarters of 2012, Apple’s total sales outpaced NPD’s domestic number by 12 percentage points,” AppleInsider reports. “Based on that Munster, is estimating that Mac sales will be up 5 percent year over year in the September quarter, which would imply sales of 5.1 million Macs.”

AppleInsider reports, “Apple’s previous record for the September quarter came last year, when the company reached sales of 4.9 million Macs. The Mac maker’s all-time record came in the holiday quarter of 2011, when Apple sold a total of 5.2 million desktops and notebooks.”

Read more in the full article here.

[Thanks to MacDailyNews Reader “Dan K.” for the heads up.]