For example, the change to a Harmonized Sales Tax to replace Provincial sales taxes in some Atlantic Canadian provinces caused prices to change. The imposition of a bottle deposit fee raised the retail shelf price by the amount of the fee. A year or so ago, the Nova Scotia Liquor Commission changed its pricing formula with respect to spirits which caused a substantial reduction in the retail price of many liquors. Or, there may be a change in what is included in the retail shelf price. In liquor stores in Atlantic Canada, the sticker price is the total price of the product.
Exchange rates change.
For example, of late the French Franc has declined relative to the Looney. Prices of French wines sold for French Francs declined recently in Nova Scotia to reflect the declining value of the French Franc. Even if the supplier charges for his product in Canadian dollars, exchange rates will have an effect on retail prices. Eventually they gave up hope that the Canadian dollar would recover any time soon, and began raising their prices. To make this already depressingly complicated subject worse, more than one of these causes may be operating at or about the same time.