Two years before he announced he was running for president, Trump released a small tweetstorm about the iPhone.

It actually began on Facebook, in April 29, 2013, when he shared with his friends and followers that he was long Apple (AAPL):

“I have a lot of @Apple stock—and I miss Steve Jobs. Tim Cook must immediately increase the size of the screen on the iPhone. It should be slightly larger than the Samsung screen—and they better get it right fast because they will lose a lot of business. I like the larger screen.”

Trump didn’t say what he meant by “a lot” of Apple, but it wouldn’t be out of character for him to put a Trump-load of chips on the table.

He picked up the theme on Twitter, (TWTR) the platform he would later adopt as his favorite way to speak directly to, and get feedback from, the American voter. (See the The New York Times’ Pithy, Mean and Powerful.)

But back to Apple, and Trump’s obsession with the size of his iPhone’s screen.

Let’s follow the tweets:

• I can’t believe Apple isn’t moving faster to create a larger iPhone screen. Bring back Steve Jobs! July 24, 2013
• As an addition, Apple must go to a larger screen now—asap! They’re losing their standing in the market! Oct. 14, 2013
• Apple’s iPhone sales fell way short-they must go to a larger screen, as alternative, fast (as I said long ago)! Samsung’s size much better. Jan. 28, 2014
• I predicted Apple’s stock fall based on their dumb refusal to give the option of a larger iPhone screen like Samsung. I sold my Apple stock Jan. 28, 2014
• Steve Jobs is spinning in his grave—Apple has lost both vision and momentum—must move fast to get magic back! Jan. 28, 2014
• I wonder if Apple is upset with me for hounding them to produce a large screen iPhone. I hear they will be doing it soon—long overdue. March 24, 2014

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[Apple unveiled the large- and larger-screened iPhone 6 and iPhone 6 Plus five and a half months later.]

Did you catch the Jan. 28, 2014 tweet that mentioned the sale of Trump’s Apple stock? That would have been right after a mixed earnings report that shaved $30 billion off Apple’s market value.

How’d that trade work for Trump? Let’s do the math:

He tweeted that he was long Apple in April 2013, when the stock was trading for (split adjusted) $58.06, and he tweeted that he’d sold it by Jan. 28, 2014, when it was trading for $69.68. It closed Monday at $117.75.

If we assume the trades took place on the same day as his tweets, Trump realized a 20% gain but passed up a chance for 103%.

He was a winner, but he could have been a much bigger winner.

Follow Philip Elmer-DeWitt on Twitter at @philiped. Read his Apple coverage at fortune.com/ped or subscribe via his RSS feed. You might also want to subscribe to Data Sheet, Fortune’s daily newsletter on the business of technology.

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