Party City is staffing up for Halloween by hiring 25,000 employees and opening 270 pop-up locations. It's an important time for the NYSE-traded company: one-quarter of its annual revenue is generated around this holiday. Party City's Chief Financial Officer Daniel Sullivan says 7 percent of annual retail revenue happens in the five days leading up to Halloween. Sullivan says the way Party City stands out in this category is by offering a product people can't get anywhere else. Party City is planning to open 300 new locations over the next 5 years. Sullivan says he's found 60 to 70 percent of people prefer to shop in-store for Halloween costumes and paraphernalia, which makes its brick-and-mortar presence even more important.