Up untill a week ago Nofrills carried these "three packs" of salmon for $10. Now the same pack contains two for the same $10. I thought it felt light when I bought it yesterday.
This comes to about $0.02 increase per gram, and a $1.10 price increase overall. Or a 11% increase in price overall. Meanwhile inflation is at 6-7%?
The old fish costs $3.92 per 100g, the new fish $5. That's a price increase of (255/200 - 1) = 27.5%.
The difference per gram (which isn't of interest to anybody) is 5-3.92, i.e. ¢1.08. Which also equates to a (5/3.92 - 1) = 27.5% increase.
Not sure what you were calculating, but every result was wrong.
and yet every single online grocery shopping I've been on refuses to have a filter or sort by price per weight option. It's even more incredibly infuriating when you have to click into an item's description or calculate it yourself, extra bonus hell points to the sites that change the weight metric so it's an extra step to figure out what the actual comparison is (probably more a US problem with ounce/pound conversion).
I just wish the weights were consistent across similar products. I've seen some supermarkets where one brand uses cost per gram while another brand uses cost per 100 grams, and yet another brand uses cost per kg, all for the same product. Some toilet papers are cost per sheet, some are cost per 100 sheets, some are cost per roll. In the USA, one item might use price per ounce while the product next to it uses price per pound. Some packs of soft drink cans use price per can while others use price per 100mL or per fluid ounce.
Unit pricing is mandated in many jurisdictions, however many of them don't mandate the specific units that are used. I wish they'd do that so that we could properly compare items.
The marketing law in Denmark does that. With few exceptions, everything must have the price displayed in the proper unit (liter, kilogram, meter, square metres or cubic metres) in addition to the price pr. item.