iPhone 5′s impact on U.S. economy estimated at $75 billion in 2012

Apple’s (AAPL) most recent smartphone launch was its biggest ever by a wide margin. The company sold more than 5 million iPhone 5 handsets during its first three days of availability, and iPhone sales across all models in the iPhone 5′s debut quarter totalled 27 million units. Apple’s latest iPhone isn’t just a big deal …