FORTUNE -- In the analysts' notes to investors leading up to Apple's (AAPL) quarterly earnings report next week, the iPhone is topic No. 1.
And with good reason. iPhone sales remain the company's single biggest source of revenue -- 52.6% of total revenues, to be specific, at this time last year.
In a note issued Wednesday, Bernstein's Toni Sacconaghi rattled off a list of imponderables that are pulling his iPhone unit sales estimate (38.8 million) in several different directions:
"Combined," he writes, "these factors lead us to believe there is more downside risk than upside risk to our estimates."
On the other hand, Morgan Stanley's Katy Huberty reported Thursday that her AlphaWise smartphone tracker, which gathers sell-through data by analyzing Web searches, indicates iPhone demand at 40.6 million units, well above her 38 million estimate. "Recent promotions," she writes, "like those at U.S. carriers and retailers, and product adjustments, notably the introduction of an 8GB iPhone 5c in some regions, may have stimulated demand more than expected."
It's certainly more than expected by most of the analysts we polled in our quarterly survey, now in its sixth year.
We've heard from 32 Apple analysts so far -- 20 Wall Street professionals and 12 amateurs. Their estimates range from a high of 42.5 million iPhones, from Needham's Charlie Wolf, to a low of 34.05 million from a pro who asked that his name and affiliation not be used. He's one of 10 analysts who believe Apple sold fewer iPhone last quarter than the 37.4 million it sold in the same quarter last year.
The average of all the estimates is 38.2 million, which would represent a 2% increase year over year. As usual, the amateurs are more bullish, with an average estimate of 38.8 million. But the pros are right behind them at 37.8 million.
We'll find out who was closest to the mark when Apple reports its fiscal Q2 2014 earnings after the markets close on Wednesday, April 23.
Below: The individual analyst's estimates -- pros in blue, indies in green. Thanks as always to Posts at Eventide's Robert Paul Leitao for pulling together the Braeburn Group numbers.
The gap Morgan Stanley spotted could be the difference between ho-hum Q2 and a blowout.
FORTUNE -- The vertical gap between the black triangle and the blue square at the far right of the attached chart -- sent to clients Wednesday by Morgan Stanley's Katy Huberty -- may not look like much.
But it represents 4 million iPhones, the difference between the Street's estimate of iPhone shipments in the quarter that ends MOREPhilip Elmer-DeWitt - Mar 19, 2014 11:14 AM ET
Meanwhile, institutional ownership of Amazon, Google and Microsoft are near record highs.
FORTUNE -- Apple (AAPL) is an outlier in a major shift of stock ownership that's unfolded over the past five years, according to a note issued Wednesday by Morgan Stanley's Katy Huberty.
She writes that as small investors took their money out of stocks and put it into mutual funds, institutions were picking the slack. Average institutional ownership of the S&P MOREPhilip Elmer-DeWitt - Feb 26, 2014 12:18 PM ET
Last week, Bernstein's Toni Sacconaghi put Apple's incremental sales at 15 million.
FORTUNE -- This week's burning question among Apple (AAPL) analysts is this:
If and when China Mobile (CHL) begins selling iPhones to its 759 million subscribers, how many will it sell in the first year?
Everybody's got numbers, but the two most persuasive estimates I've seen came from Bernstein's Toni Sacconaghi and Morgan Stanley's Katy Huberty, who each took the time to show his or MOREPhilip Elmer-DeWitt - Dec 16, 2013 10:22 AM ET
Apple's iPad now trails Android in both units shipped AND revenues, says Morgan Stanley.
FORTUNE -- Apple (AAPL) investors have long taken comfort in the fact that even if its share of tablet shipments fell behind Android's in a particular quarter, the company still took home the lion's share of tablet revenues.
That's no longer true, says Morgan Stanley's Katy Huberty.
Working from the tracking numbers IDC released two weeks ago -- which MOREPhilip Elmer-DeWitt - Nov 15, 2013 8:27 AM ET
Morgan Stanley's chief Apple watcher likes what she sees.
FORTUNE -- Three months ago, Morgan Stanley's Katy Huberty predicted that Apple (AAPL) would sell 34.5 million iPhones in the quarter that ended Sept. 29. In the note she sent to clients Friday she stuck with that estimate -- even though she writes that demand last quarter was probably closer to 37 million.
Except for the "supply constraints" that she believes limited the MOREPhilip Elmer-DeWitt - Oct 18, 2013 7:33 AM ET
In a survey of 799 U.S. customers, 12% of iPhone owners said they might buy one.
FORTUNE -- Apple (AAPL) does not sell a smartwatch. It hasn't introduced one or said anything about making one. But it has filed patents for a computerized touchscreen wristband, and this summer it registered the iWatch trademark in half a dozen countries.
On the strength of that, Piper Jaffray's Gene Munster recently set out to gauge MOREPhilip Elmer-DeWitt - Oct 7, 2013 7:29 AM ET
AlphaWise survey data through Sept. 15 catches early interest in iPhones 5C and 5S.
FORTUNE -- Apple (AAPL) had only just begun taking iPhone 5C pre-orders Sunday when Morgan Stanley's AlphaWise Smartphone Tracker closed the books on Q3 2013, but the survey had already registered a bump in buyer interest in the company's line of smartphones.
According to a note to clients posted early Wednesday by Morgan Stanley's Katy Huberty, the survey's data suggest MOREPhilip Elmer-DeWitt - Sep 18, 2013 6:24 AM ET
In North America, 77% carry iPhones and 57% own Macs.
FORTUNE -- There were several surprises in Katy Huberty's summary Friday of a survey of 530 Morgan Stanley summer analysts and associates in North America (NA), Asia Pacific (APAC) and Europe, the Middle East and Africa (EMEA).
First, who knew that Morgan Stanley hired so many summer interns?
And who knew that they were so devoted to Apple's (AAPL) products?
Huberty doesn't make a MOREPhilip Elmer-DeWitt - Aug 23, 2013 6:22 AM ET
AlphaWise survey finds Chinese willing to pay up to RMB 4,000 ($486) for the Apple brand.
FORTUNE -- Morgan Stanley's Katy Huberty has some good news for Apple (AAPL) and bad news for everybody else trying to sell smartphones in China.
On Monday, the same day the Wall Street Journal put its imprimatur on rumors that have been floating around for weeks -- namely, that Apple is set to launch a pair MOREPhilip Elmer-DeWitt - Aug 20, 2013 4:37 AM ET
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