If I look at the 1960’s, I can see a distinct style of fashion and furniture, as I can with the 70’s, 80’s, etc. Did ancient Romans have the same change of domestic tastes every decade, or did trends change on a slower basis?

So this will likely need someone more experienced or at least recently read on this subject to weigh in but I'll offer my recollection. Also, looking into my source I believe my class really only focused on the painting styles or at least I have a less vivid recollection of the other forms of art and decoration.

Much work has been done in Pompeii to look into trends such as those you're after. Within excavated homes there have emerged 4 distinct styles of wall decoration (painting) which show an evolution and stylistic change making them very distinct from one to the next. Looking up a quick chart of reference homes and their dated paints, it appears that these trends stretched from ~175 BCE through the burial of Pompeii in 79 CE. I'd say it roughly breaks down as -

Style 1 - 75 or so years in vogue. Style 2 - 120 or so years. Style 3 - 40 or so years Style 4 - 30ish years (or until eruption)

These trends and the general evolution of the style was fascinating to me. I highly recommend looking into it further. The gist is that the first style was a trend carried over from Greece in which is was common to build with multi colored marble. Lacking this material, Roman homes would simply paint colors on the wall in either patterns or other patchwork blocks of solitary color. Second style added images to the painting, generally first enhancing the architectural appearance (arches or other flourishes) and extending to adding vistas as if you were looking through the wall into an open space or garden. Realism in depiction was somewhat sought after. The third style took this further and began to frame these images and relegate them into non standard areas of the wall (simply meaning not where you'd expect a window or other opening, often higher up) with other designs or colors implemented lower down. The depictions in the images began to also get more sureal in this phase. Fourth style, I honestly always had trouble distinguishing this one but I believe it was just a more contrasted version of third style, mainly an effort was taken to very much contrast pictorial flourish with the other decoration on the wall, and often blur where the art met the architectural enhancements or other framing.

Anyway, I think it is safe to say that it is likely the Empire experienced a similar change of trends as it evolved and time went by. What's interesting to me is it seems this was speeding up in the first century CE though with Pompeii as an example we obviously don't have the long term data to confirm if this trend continues. As I'd imagine much of this decoration was much more work intensive and costly than today, not to mention general technology at the time making it likely much slower for trends to spread, I don't think it odd that it seems ~75-~40 years may have been more in line with the changes in trend.

Source: 'Domestic Decoration: Painting and the "Four Styles"' by Volker Michael Strocka

Included in an amazing book of cross discipline and topical articles on Pompeii, the event, the history of excavation and a ton of insight that has been gathered about Roman life from the site. 'Th e World of Pompeii' edited by John J. Dobbins and Pedar W. Foss.

Pre-edit: browsing through the article on Mosaics and Stucco it appears these also followed similar changes in style. And I do now recall we touched on mosaic differences which I believe also went from more simple and decorative shapes/patterns and eventually moved towards more image based depictions of famous events as you may have seen in a museum. Unfortunately there's no awesome chart to give me an eyeball of change in trend over time.