Year on year only makes sense for economists, it doesn't make sense for regular people, hence all the comments every time they report the numbers saying "Yeah well my grocery is up X%, rent is up Y%, gas Z%, that's a whole lot more than what they're reporting!"

People live inflation long term, not on a yearly basis and those who are lucky enough to be unionized negotiate their wage increase over multiple years, not every year, both numbers are important, it's still dishonest to only report the year on year increase when people still have it fresh in mind that lettuce was 99 cents not too long ago and it's been over 4$ for years now, to them inflation isn't 3%, it's 400% on lettuce, the fact that it's stagnated for the last year means nothing on their budget when they suddenly had a hard time buying and they still have a hard time buying it.

Another example, housing is starting to stagnate if not depress in some markets, do you really think that people feel like they can trust economists when they're told "There's deflation in the housing market in your region." when they look at the price of a house that was selling for 300k five years ago when they were ready to buy and couldn't afford it and that's now on the market for 800k instead of 850k line it would have been 6 months ago? Sure, year on year there's deflation, it doesn't mean shit when you're trying to purchase a good that you want to own long term and all you see is that you still can't afford it because wages have been stagnating.

Heck, take actual wages into consideration and inflation is a hell of a lot worse than what's presented in the news! If prices stay the same but wages go down, it will get reported as inflation being 0% when in fact it's positive!