Piper Jaffray analyst Gene Munster estimates that Apple sold 10 to 10.5 million iPods in its fiscal second quater (January, February and March). Munster views this data point as a "slight positive, given recent Street chatter of a very weak iPod number for the quarter." The Piper Jaffray analysis looks at the percentage contribution in NPD data from each month of the quarter in past March quarters. The analyst says that the cheaper iPod shuffle drove sales in February and March. Munster previously said that the iPod will be a slower growing segment than the Mac or iPhone, and expects iPod unit growth to be flat in the calendar year 2008, but also thinks that Apple can maintain iPod unit growth and slightly exceed street expectations. Munster believes that the iPhone will replace the iPod as a driver of significant growth for the company.