That sick yin-yang tattoo you got in the mid-90s? Sorry, it's going to take 10-15 sessions, at $200 a pop, to remove.

Stonehill/Corbis

o ink or not to ink? This week, the American Medical Association published what's considered to be the first scientific survey of tattoo removal, detailing which tattoos are hardest to remove (blue ink) and what factors reduce the odds of erasing the damn thing (smoking). The report is a sure sign that tattoos — once the province of rock stars and ne'er-do-wells — have become thoroughly mainstream. Indeed, today not only are tattoo artists enjoying a robust growth-industry, their counterparts — the tattoo-effacement experts — are busily tending to Americans who regret that faded tribal design encircling their biceps or have discovered that the Chinese character on their wrist has an unwelcome meaning. Here, a numerical guide to America's tattoo obsession:

$2.3 billion
Annual revenue of the tattoo industry

15,000
Tattoo parlors in America

21
Percent of Americans who have a tattoo

23
Percent of women who have a tattoo

19
Percent of men who have a tattoo

36
Percent of 18-to-25-year-olds who have a tattoo

38
Percent of 30-to-39-year-olds who have a tattoo

11
Percent of 50-to-64-year-olds who have a tattoo

50 
Percent of people who think having a tattoo is rebellious

$80 to $100
Average per hour cost of a tattoo

$150-$350
Per hour cost of a tattoo in Brooklyn, N.Y.

$200
Cost of a laser tattoo removal session

10-15
Sessions needed to remove a tattoo

32
Percentage increase in tattoo removals over the last year

Sources: Harris Interactive, Mental Floss, The Motley Fool, NBC News, Pew Research Center, Tattoo Info, The Wall Street Journal (2)