A good publicist is the catalyst in the mathematical formula that determines the longevity of celebrity, according to Mark Borkowski, author of "The Fame Formula: How Hollywood's Fixers, Fakers & Star Makers Shaped The Publicity Industry". The formula is this:

F(T) = B+P(1/10T+1/2T2)

It's too complicated to go in to here, but you can read an excerpt of the book to be published tomorrow in the U.K. on the Guardian's site.

According to Borkowski's theory, each spike of fame lasts fifteen months, unless stoked anew through the good storytelling of a publicist. He crunched the numbers on some big names and found it to be accurate including Angelina Jolie, Tom Cruise, Mel Gibson, and even Hugo Chávez, as well as brands like Red Bull, Stella Artois, Heineken, American Express and Adidas.

The chapter gives props to PR heavyweights Pat Kingsley, Stan Rosenfield, and the Rogers & Cowan agency for understanding this, and shaping great narratives for the public to enjoy about their clients.

(continued after the jump)

Probably the best case study of cyclical, phoenix-like rebirths is Madonna, dating back to before a fair number of celebrity flacks were born:

Madonna is an excellent example of a celebrity working the fame formula to perfection. From her early days as a sharp-witted 80s party girl, she has moved onwards and upwards in her quest to stay famous, creating controversy through videos of her kissing a black Jesus, her Sex book and her flirtation with lesbianism, changing style for every album, acting parts in movies, adopting children, writing books for children and becoming a member of the English landed gentry by dint of marriage and money. Even her sporadic film roles, lambasted though many of them have been, are part of her success. Each new innovation has caused her fame to spike and kept her in the media spotlight.