FORTUNE -- Needham's Charlie Wolf has been following Apple (AAPL) long enough to still care what's happening to the Mac,* and on Tuesday he took a crack at explaining why the company's most venerable product line (it turns 30 in January) seems to have, as he puts it, "fallen back to earth."
Beginning in 2005, and for 26 quarters in a row, Mac sales outgrew the industry -- nearly coinciding with a 7.5-year stretch in which Apple's share of the worldwide PC market increased from 2.1% to 5.3% (152%) and its revenue share rose from 3.2% to 11.9% (272%).
That streak ended abruptly in January, when Apple couldn't deliver the newest iMacs in sufficient quantities to meet demand. Mac sales fell 22.1% in a quarter in which the broader market fell 6.6%.
Wolf is less concerned with that one-time event -- which Tim Cook admitted was a screw-up and which appears in the attached chart as a sharp V at calendar Q4 2012 -- as he is with what happened for several quarters before and after.
The Mac is still outpacing the industry, but just barely and only because its sales are falling more slowly than everybody else's.
Why PC sales growth has collapsed is no mystery. The market is largely saturated and most of the money for new purchases is being funneled into smartphones and tablets.
Harder to explain is why the Mac, which used to outgrow the industry by 20% to 30%, is now shrinking at nearly the same rate.
Wolf confesses that he has no "ready explanation," but he does offer a couple of theories:
*For the record, the Mac generated $21.5 billion in revenue for Apple in fiscal 2013, 13% of the company's total sales and more than the total revenue of 368 of the companies in the Fortune 500.
According to Asymco's Horace Dediu, whom Wolf quotes, the Mac's share of PC profits was 45% in March, almost equal to the profit share of all Windows PC companies combined.
The analysts' estimates range from 3.6 million to 5 million. Average: 4.26 million.
FORTUNE -- Apple's (AAPL) Mac sales haven't been hurt as much as Windows PC's have by the rise of tablets and smartphones. But Mac shipments peaked in late 2011, and the best Apple can probably hope for now is that they hold up better than everybody else's.
The analysts we polled in advance of Monday's fiscal fourth quarter earning report MOREPhilip Elmer-DeWitt - Oct 26, 2013 10:31 AM ET
Software hasn't just supplanted hardware in the past decade. It needs hardware as an ancillary business.
By Kevin Kelleher, contributor
FORTUNE – Imagine it's 1999. Scratch that, it's 2006.
The computer in your office is made by ... well, it doesn't matter who it's made by. Unless you are in a creative profession, that computer is run on Microsoft Windows. And the phone in your pocket is made by Nokia (NOK), or -- MORESep 4, 2013 10:02 AM ET
Even as Lenovo was becoming the top seller of PCs, its sales of mobile devices were surpassing its sales of computers.
FORTUNE -- In yet another data point highlighting the worldwide shift from PCs to tablets and smartphones, Lenovo (LNVGY) says its sales of mobile devices have surpassed its sales of PCs.
Sales of "smart devices" (including phones, tablets, and PCs) rose by 41% in over the past year, Lenovo said in MOREDan Mitchell, contributor - Aug 15, 2013 1:13 PM ET
It's hard to put a finger on what's amiss with the new gesture-based computing peripheral from Leap Motion.
By John Patrick Pullen
FORTUNE -- He shot me. After a good eight seconds of flailing, grabbing, and poking at the air above my desk, Frank Welty finally unholstered his sidearm and put me out of my misery. Alas, it was only a game, but I never really stood a chance. My shooter, MOREAug 6, 2013 5:00 AM ET
In the context of the industry's longest slowdown, the numbers could have been worse.
FORTUNE -- According to Gartner, worldwide PC shipments fell 10.9% last quarter, the industry's fifth consecutive quarter of decline. According to IDC, shipments are down 11.4% year over year, capping the industry's longest slowdown ever.
The main thing that's hurting PC sales, both research firms agree, is that customers who used to buy PCs are buying tablet computers instead.
In MOREPhilip Elmer-DeWitt - Jul 12, 2013 6:48 AM ET
The Chinese tech company is one of the biggest companies in the world.
FORTUNE -- As widely expected, China's Lenovo this week emerged as the world's top purveyor of personal computers, according to new reports from two research firms. Both Gartner and IDC say Lenovo's market share in the second quarter of 2013 hit 16.7%. Lenovo unseats longtime No. 1, Hewlett Packard, whose share fell to 16.3%, Gartner says.
Lenovo had another MOREStephanie N. Mehta, Deputy Managing Editor - Jul 11, 2013 7:48 AM ET
The growth in wearable computing could also be a new source of profits.
FORTUNE -- Intel was slow to enter the mobile market, but the chipmaker says it is now taking steps to speed up development of its Atom chip line for mobile devices. It's also rushing ahead to provide silicon (and services) to another potentially hot market: wearables, a new product category which includes connected glasses and watches.
The company's top MOREMichal Lev-Ram, writer - Jul 1, 2013 10:04 AM ET
Hardcore PC gaming appears to be alive and kicking.
By Peter Suciu
FORTUNE -- While Microsoft and Sony elaborated on their new video game consoles earlier this month at the Electronic Entertainment Expo there was another system that showed signs of renewed life: the PC. Despite the moribund market for mainstream computers, hardcore PC gaming seems to be alive and well.
In past years the PC had been a dominant part of MOREJun 26, 2013 11:42 AM ET
Android is tops in mobile phones, Windows in PCs. Apple has a pony in both races.
FORTUNE -- Worldwide shipments of PCs, tablets and mobile phones will grow 5.9% to 2.35 billion units in 2013, according to a report issued Monday by Gartner Inc.
But that growth is not uniform. Breaking down the 5.9% number, Gartner estimates that traditional PC shipments will fall 10.6%, mobile phone shipments will grow 4.3% and tablets MOREPhilip Elmer-DeWitt - Jun 24, 2013 7:39 AM ET
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