For the last several years, Apple has kept analysts, customers, investors, and others in the dark on exact device sales. The Q3 quarterly Mac numbers confirm that the process of estimating product shipments is very inexact.

The estimates of how many Macs Apple sold in the third quarter are vastly different from those of other companies.

It is estimated that Apple sold 10 million Macs during the quarter, up from 7 million in the year-ago quarter. Apple sold 5.8 million Macs in the most recent quarter, which is down from 6.9 million in the year-ago quarter, according to a report by research firm.

There is a 4.3 million Mac shipment discrepancy between the estimates from the two companies. According to Canalys, Apple shipped 8 million Macs in the most recent quarter, up from 7.9 million in the year-ago quarter.

We have historically seen discrepancies between estimates, but not this much. During its October 27 earnings call, Apple will give more data on its revenue for the third calendar quarter, which should give us a better idea of how the Mac sold.

The new M2 MacBook Air and M2 MacBook Pro were offered by Apple this quarter, but it was also facing delays due to supply chain issues. Apple won't give unit sales information, but overall Mac revenue will clear things up, at least in terms of year over year sales and revenue.