This week, rich and famous human Lena Dunham will begin her 12-city book tour. Several dates will feature regular people performing. They will not be paid. Let's do the math on that. (Updated below.)

From the New York Times' writeup of Dunham's tour:

Last month, the writer, actor and producer Lena Dunham started an ambitious project. Nearly 600 people responded to an open call for video auditions on her website, including a sand artist, a ukulele player, a cappella singers, gymnasts, performance artists and stand-up comics, even some exceptionally charismatic babies.

The seven who made the final cut won't be making cameos in "Girls," Ms. Dunham's HBO show about Brooklyn 20-somethings. Instead, they'll be the warm-up acts — performing free of charge — on an elaborately produced, 11-city tour to promote Ms. Dunham's new book, "Not That Kind of Girl."

Forbes' estimate of Lena Dunham's annual earnings: $6 million

Lena Dunham's book advance: $3.7 million

Tickets sold for Lena Dunham's book tour: 8,000

Price per ticket: $38 (or $900, from scalpers)

Total book tour ticket revenue: $304,000

Percentage of book tour revenue reserved for regular people performing as warm-up acts for Lena Dunham: 0%

Number of minutes that Lena Dunham would need to spend writing in order to earn the money that will be paid to the warm-up acts on her upcoming book tour: 0

Update: Caroline Bassett, a comedian who is opening for Lena Dunham on October 12 in Austin, told us this: "I'm fine with not being paid because of the circumstances surrounding the event — I essentially volunteered by applying. I have a chance to work with someone whom I respect and who's highly accomplished, which is rare for someone at my level. It'll be a unique addition to my credits. That's plenty, and on top of that, I get to tell jokes aimed at Christian Mingle and the Church of Latter Day Saints in a chapel full of Austin women. Heaven on Earth. I don't really understand why people are getting upset about it on my behalf."

Update 2: Lena Dunham has decided to pay her opening acts.

[Photo: Getty. Are you performing as an unpaid warm-up act on Lena Duham's book tour? Email me.]