There's a magic number that makers of everyday goods are obsessed with: $9.99. Just a penny more and shoppers start to turn away. Keeping prices under $10 has long been a strategy used by U.S. retailers. It is a tried-and-true price point that encourages people to switch brands and try new products, from soap to soda, pain relievers to party favors.

And it's more important than ever with many Americans feeling stretched by inflation. But it's getting harder for companies to keep products under that price point. Higher fuel prices, tariffs and other factors are driving up the costs for making products.

That is forcing many companies to drive hard bargains and sacrifice profit margins to hold prices below the psychologically important $10 threshold. Companies are redesigning packaging and slashing marketing budgets to maintain the psychologically important threshold.