Will Lowered Mac Prices Boost Unit Sales as Piper Jaffrey Thinks?

According to Piper Jaffrey analyst Gene Munster, Wall Street doesn't appreciate the sales boosting power that price cuts on Apple's notebooks will have on Mac unit sales. But it may be that investors have become wary of Munster's predictions, as they are often significantly off the mark. And, in this case, there is additional evidence suggesting against the sudden appearance of increased price elasticity. First, to Munster's prediction:he upped his estimates of unit movements:

"The big picture" is that "[we] believe the Street is underestimating the positive impact of Mac price cuts announced on June 8th," he wrote. "As such, we expect the June quarter to mark the trough for Mac unit growth rates through the balance of CY09 and we believe the Street is not fully appreciating the positive impact of these price cuts on unit growth."

• from 2.5 million to 2.8 million Macs
• from 10.8 million to 11 million iPods
• from 4.1 million to 5 million iPhones

Next, right before the Apple World Wide Developers Conference, Munster said that it could be a slight disappointment for a few reasons, including the following:

• No new line of iPhones would be announced until mid-July.
• A low-end iPhone would only drop to $149, not $99.
• There would be no "wow factor" over Mac OS X Snow Leopard.

In other words, just because Gene Munster says it's so isn't a good reason to place a bet. But ultimately this is a negative variation on a rhetorical appeal to authority. So let's look at the idea of a price drop being a big sales stimulus. It's essentially a guess that Macs have far more price elasticity than those on the Street generally think. However, there's evidence to the contrary. We've seen that net sales per unit have been slipping at Apple. Look at this table:

NPD Mac US sales graph via Fortune.