AT&T's 1.6 million activations equals 3.7 million iPhones - Analyst

AT&T (T) released its first quarter results Wednesday morning, and although earnings were down 9%, its iPhone business was strong, with more than 1.6 million activations in the quarter.

According to Piper Jaffray's Gene Munster, that's good news for Apple (AAPL). In a brief report to clients he calculates that 1.6 million activations translates -- once Apple Store and international shipments are added in -- into sales of 3.7 million iPhones.

How does he figure that?

"Last quarter," he writes, "AT&T activated 1.9 m[illion] iPhones and Apple sold a total of 4.4 m[illion] units. According to this relationship, the AT&T activation number implies a total of 3.7 m[illion] iPhones in the March quarter."

That would be a positive sign for Apple shareholders, says Munster, because the Street is expecting the company to announce later Wednesday that it shipped 3.3 million iPhones in the quarter.

Strong iPhone sales are also good news for AT&T. 40% of those new activations came from customers who were new to the carrier. Once on board, iPhone customers tend to stay loyal (reducing "churn") and generate an average 1.6 times more revenue than other customers.

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