Apple sales data: Half empty, half full

It continues to amaze me that analysts who specialize in Apple (AAPL) can look at the same data and come to such different conclusions.

Case in point: Reports issued Tuesday morning by Bernstein Research’s Toni Sacconaghi and Piper Jaffray’s Gene Munster. Both analysts examined the latest NPD data — released a day before Apple’s fiscal Q1 earnings call — but they didn’t see the same thing.

“Sales Weak,” begins the headline in the report by Sacconaghi, who has a history of bearish predictions for Apple. Based on the latest data, he is lowering his earnings and revenue estimates for both the quarter and the year.

“iPod & Mac Appear Solid,” counters Munster, one of Apple’s strongest supporters. Munster is sticking with his price target of $235 per share. The stock opened Tuesday at $81.97.

The NPD Group tracks retail sales for a broad range of products — including computers and MP3 players — and issues monthly reports that analysts pore over with the kind of attention Nathan Detroit lavished on parimutuel odds.

On Monday, NPD reported that December Mac sales were up slightly from a month earlier. This is how Muster reported it:

“In-Line Results A Positive Surprise. We have analyzed NPD data for all 3 months of the Dec. quarter (Oct., Nov., and Dec.) which is up 8% y/y, in line with the Street at 8% (we believe Street consensus is ~2.5m Macs in the quarter). We believe this data will be perceived as a slight positive given the rebound in the month of Dec. to +4% y/y, up from -1% y/y in the month of Nov., which some investors were using as an assumption for Dec.”

Here’s Sacconaghi’s take:

“Mac. NPD data showed a significant deceleration in U.S. retail sales in November (1% y/y decline; see Exhibit6); desktop sales were particularly disappointing, with units down 38% y/y (in part reflecting a difficult compare). Data from Gartner and IDC suggests the market did not get any better in December.”

This theme continues throughout their reports. Sacconaghi sees “significant deterioration” in iPod sales from the NPD data. Munster believes “the segment’s outperformance relative to Street expectations is a positive.”

Both analysts see the iPhone as a wild card, expecting international sales to offset what Munster calls “headwinds” in the U.S. market. But NPD doesn’t provide data for cell phones, so the analysts were on their own.

Not surprising, their iPhone sales estimates are wildly divergent. Sacconaghi is calling for sales of 3.5 to 4 million units in the quarter that ended in December. Munster is sticking with his estimate of 6.4 million, but acknowledges that it might prove to be “aggressive.”

Their estimates for Macs and iPods, on the other hand, are not so far apart.

Bottom line, for 2009 Q1: