Apple’s Safari browser, like rival Internet Explorer (IE), has lost a significant number of users in the last two years, data published Wednesday showed.

The most likely destination of Safari defectors: Google’s Chrome.

According to California-based analytics vendor Net Applications, in March 2015, an estimated 69 percent of all Mac owners used Safari to go online. But by last month, that number had dropped to 56 percent, a drop of 13 percentage points—representing a decline of nearly a fifth of the share of two years prior.

It was possible to peg the percentage of Mac users who ran Safari only because that browser works solely on macOS, the Apple operating system formerly labeled OS X. The same single-OS characteristic of IE and Edge has made it possible in the past to determine the percentage of Windows users who run those browsers.

, particularly IE, during the same period. From March 2015 to February 2017, the use of Microsoft’s IE and Edge on Windows personal computers plummeted. Two years ago, the browsers were run by 62 percent of Windows PC owners; last month, the figure had fallen by more than half, to just 27 percent.

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Simultaneous with the decline of IE has been the rise of Chrome. The user share of Google’s browser—its share of all browsers on all operating systems—more than doubled in the last two years, jumping from 25 percent in March 2015 to 59.5 percent last month. Along the way, Chrome supplanted IE to become the world’s most-used browser.

, and told customers they must upgrade to IE11. Faced with that, many instead simply deserted to Chrome.

Apple did not make that same mistake, so reasons for Safari’s decline are muddier. One possibility: Those who used both Windows and OS X/macOS—perhaps one at work, the other at home—may have shifted to the common denominator of Chrome for the convenience of bookmark and password synchronization. Under that theory, a small increase of Chrome on OS X/macOS was simply a side effect of the much larger rise of Chrome on Windows.

This story, “Safari browser sheds users, mimicking IE” was originally published by
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