For at least a decade, we’ve heard about the one-in-eight chance that a woman will get breast cancer. Scary. But it sounds worse than it is.

“Some people might think the one-in-eight chance reflects the likelihood of their getting cancer in the next few years,” says Ted Gansler, M.D. “But what it actually means is that your lifetime risk, from birth to the average life expectancy of 80, is one in eight.”

Another way of looking at it is that out of all women born today, 12.7 percent (about one in eight) will be diagnosed with breast cancer at some point in their lives. The older you are, the higher your chances are of developing breast cancer over the next few years. The average age at detection is 61.

Here’s a breakdown from the National Cancer Institute of what the numbers are for your actual risk.

From age 30 through 39, you have a 0.43 percent (1 in 233) chance.

From age 40 through 49, you have a 1.44 percent (1 in 69) chance.

From age 50 through 59, you have a 2.63 percent (1 in 38) chance.

From age 60 through 69, you have a 3.65 percent (1 in 27) chance.

You’re Less Likely to Get Breast Cancer If…

You’re short. Scientists haven’t figured out why, but taller women have a slightly higher risk.

You began menstruating after age 11.

You haven’t used hormone-replacement therapy for longer than five years.

You’ve given birth, especially before age 30.

You breast-fed for at least six months.

You’re a man. (But the American Cancer Society estimates that 1,720 American men will be diagnosed with breast cancer in 2006.)

You have less than one alcoholic drink a day.

You’re not currently taking birth control pills.

You maintain a healthy weight.

You exercise regularly.