The Mac is poised to break Apple's annual sales record, according to an analysis of past sales trends as well as Wall Street projections.

The increase is a strong signal that Apple does have an opportunity to grow not just short-term sales, but to capture a larger share of the overall personal computer market, industry analysts said.

"My opinion hasn't changed, there's a lot of share to be gained by the Mac," said Ben Bajarin of Creative Strategies today. "As consumers get back into the game, you can make the case that while tablets were great, I need this particular product [a device with a keyboard]. In that core group, the Mac has a strong value proposition."

Last year, Bajarin proposed that the Mac, which in 2013 accounted for just 5.6% of all personal computer sales, had a shot at reaching 20%.

While the Mac remains far from that target, it has been on an upswing. The line broke Apple sales records for both quarters this calendar year, up 5% year-over-year in the March quarter and up 17% in the June period.

That streak could continue.

Over the last three years, Mac sales in the July-September quarter have jumped an average of 22.8% from the previous three-month period -- sales fueled by back-to-school purchases. The quarter-over-quarter growth has also been exaggerated by less-than-stellar numbers in the June quarter, historically the slowest or second-slowest of the year.

Boosting the 4.4 million Macs Apple reported for the June quarter by 22.8% would produce a forecast of 5.4 million for the September quarter, a record by 500,000 machines. Building on that, and using the same methodology -- over the years sales have climbed an average of 6.1% from Q3 to Q4 -- the December quarter could be more than 5.7 million. The December period would also be a record, trumping the milestone of Q4 2011 by 550,000.

Under this scenario, Apple would sell 19.7 million Macs worldwide for the year, breaking the 2011 record of 17.8 million by, for Apple, a huge margin of about 2 million.

That would represent double-digit year-over-year growth of 15.1%, something Apple hasn't experienced since 2011, the year of "Peak PC." It would also thrash the industry average as projected by research firms IDC and Gartner. IDC, for example, has forecast a 6% decline in the global personal computer business compared to 2013; Gartner, which measures a different mix of devices, has estimated the downturn at 3%.

But double-digit Mac sales growth isn't a certainty: Wall Street forecasts for the second half of 2014 were more conservative, or more realistic, depending on one's perspective.

Brian White of Cantor Fitzgerald has pegged Q3 and Q4 Mac sales at 4.9 million and 5.1 million, respectively, representing sequential growth of 10% and 4%. For 2014, White's estimate of 18.5 million translated into an annual gain of 8.3%.

Meanwhile, Brian Marshall, an analyst with the ISI Group, was more optimistic for the holiday selling season, with Q3 and Q4 forecasts of 4.8 million and 5.5 million, or quarter-over-quarter increases of 10% and 14%. His annual total of 18.9 million was 10.5% higher than actual sales in 2013.

Even though their numbers didn't agree -- and were significantly below those Computerworld came up with its "average quarter-over-quarter gains" approach -- each analyst's projection would mean new yearly records for the Mac.

Because those estimates anticipate Mac growth in the face of a still-down market overall, Apple should increase its share of systems shipped during 2014. Using IDC's forecast of 296.3 million personal computers to be shipped worldwide this year, Apple's slice would be between 6.2% and 6.6%, or as much as a full percentage point above 2013's.

Even so, the highest 2014 share estimate of 6.6% makes the Mac no more than a small fish in a big sea. But as other analysts have pointed out, Apple rakes in most of the profits recorded by personal computer makers. With a larger market share, the trend, and Apple's revenue and profit, would climb too.