Portfolio magazine estimates Britney Spears contribution to the economy – not just direct contributions (her 80 million record sales), but indirectly as well:

To the casual tabloid reader, Britney Spears’ life looks like a train wreck. To the Britney Industrial Complex, comprising everyone from paparazzi to perfume vendors, she is a gold mine. Whether she’s shaving her head or battling for custody of her children, Britney seems to grow more fascinating (and to some people, more lucrative) every time she stumbles. Recent court documents suggest she’s amassed a $125 million fortune and continues to rake in about $737,000 a month, or nearly $9 million a year. But that’s chicken feed compared with the overall Britney economy.

They estimate (or perhaps “estimate”) the average annual contribution at around $120 million.

That might actually be a bigger contribution to the Gross World Product than Canada, when you deduct healthcare expenses.