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From what I can recall, it was WordPerfect 5.1 which dominated the business landscape for about a decade, from the late 80s well into the mid or latter 90s, far more so than any Mac application. Macs did make some headway prior to that time, and there WAS a Mac version of 5.1, but its installed base was never more than a fraction of that sported by the PC side.
This isn't to say it was any good, I hated the thing and was continually amazed at its ubiquity (I knew of certain cheap-ass lawyers who used the thing until the turn of the century, believe it or not)....but 5.1 was THE de facto standard for most of that time.