JUDY WOODRUFF: Tonight, we begin a weeklong series on reactions to the Affordable Care Act, now that Americans have had time to read the fine print.

First, we focus on a pivotal demographic needed to make the state health exchanges work, a group often referred to as young invincibles.

Our report comes from our colleagues at Wisconsin Public Television.

The correspondent is Frederica Freyberg.

GEORGIA CURRY, yoga instructor: Take a deep, deep breath in.

FREDERICA FREYBERG, Wisconsin Public Television: Twenty-five-year-old Georgia curry is a college graduate and yoga instructor.

GEORGIA CURRY: Kind of working as a freelancer in different areas at different yoga studios in fitness. And I need insurance.

Grab your left ankle.

FREDERICA FREYBERG: She says she needs insurance by next year, when she turns 26 and is no longer on her parents plan.

Curry acknowledges her work keeps her fit. She knows she’s young and healthy, but not invincible.

GEORGIA CURRY: You never know when you’re going to break your leg, if you’re going to get in a car accident. Like, you never know.

FREDERICA FREYBERG: In Wisconsin, 19 percent of 18-to-34-year-olds are uninsured. In Milwaukee, that number is 26 percent. Statewide, that’s 229,000 uninsured young people in that age group.

Brian Burrell is Midwest director of a national group called Young Invincibles, which advocates for economic security, including the Affordable Care Act.

BRIAN BURRELL, Young Invincibles: Young adults are historically just the largest uninsured age group. And so this is a huge shift. And a lot of people are in a little bit in the lower income. They will be able to qualify for some of those benefits. And the big thing is really that we actually came up with the name because we’re not invincible. Young people, they are going to get hurt, they are going to get sick at some point, and just a matter of when.

And when you compare looking at a premium that might cost you a hundred bucks, 50 bucks a month, compared with a $10,000 broken bone, there’s a big difference and it will give you some real financial security.

FREDERICA FREYBERG: But some young people just don’t buy it; 20-year-old Haley Sinklair is a U.W. Madison active in Young Americans for Liberty, staunchly opposed to the new health care law.

HALEY SINKLAIR, Young Americans for Liberty: You are being taxed or fined if you don’t sign up for health care. And that’s frustrating because never have we had something like that, where you’re mandated for health care.

FREDERICA FREYBERG: Under the Affordable Care Act, the penalty for an individual not having insurance is $95 in 2014. It goes up to $325 in 2015 and $695 in 2016.

GEORGIA CURRY: I would like to pay a really low premium.

FREDERICA FREYBERG: According only to estimates, because she couldn’t get into the online marketplace, Curry’s insurance premium for 2014 for a mid-tier plan would be $2,428 a year. But, because of her income, she could get a government tax credit of $2,188, making her premium $240 a year.

GEORGIA CURRY: I know some people who I would venture to guess will not buy insurance the first year and pay the penalty. But as the penalty increases year to year, I think you get to a point where it’s worthwhile to just pay and have the coverage.

BRIAN BURRELL: The choice that people think that they would rather pay the penalty, then they can definitely do so. But I think especially starting in 2016, the penalties will actually be quite a bit higher. It will be a minimum of $700. And so, in some instances, when you’re getting those tax credits, it could actually be cheaper just to buy health insurance.

FREDERICA FREYBERG: So, the push is on and built into the law to incentivize 18-to-34-year-olds to enroll in the health care marketplace.

We asked U.S. Department of Health and Human Services Regional Director Kathleen Falk about it.

How important is it to get this young healthy demographic though into the kind of group?

KATHLEEN FALK, U.S. Department of Health and Human Services: Well, it’s — sure, it’s important to help a bigger pool, so we all pay lower rates. We all have some skin in that game. But it’s also important because of their health.

FREDERICA FREYBERG: Insurers and providers in the marketplace acknowledge they want the young enrollees.

MICHAEL RICHARDS, Gundersen Health System: The big demographic that we’re trying to attract here with the marketplace is the young invincibles, as we call them, those people that need to get in health insurance, but may not have the chronic illnesses that somebody maybe in the Medicare age group does. So just because they will have insurance doesn’t mean they will need that care.

FREDERICA FREYBERG: Haley Sinklair says she opposes the premise.

HALEY SINKLAIR: So, I have to try to find a job to pay off my student loan debt, but also pay an exorbitant amount for these new health care premiums that will rise for young people because we’re the ones covering everyone else.

FREDERICA FREYBERG: So, what happens — and this is what supporters always talk about — you are crossing university avenue and you get hit by a car and you break your leg? What then?

HALEY SINKLAIR: Then I have to deal with those consequences because I made that choice as an individual to go uninsured. And I have to deal with the expense. And if I have to into debt again after college, I have to. That’s my individual responsibility.

FREDERICA FREYBERG: A 1986 law requires hospitals to provide care to anyone needing emergency health care treatment, regardless of ability to pay.

The new Affordable Care Act is designed to reduce that most expensive kind of treatment by incentivizing primary and preventive care, because emergency room bills add up fast, and certainly not all of those charges incurred by even the best intentioned, but uninsured young invincibles would or could be paid.

GEORGIA CURRY: I work paycheck to paycheck pretty much.

FREDERICA FREYBERG: And so for young people like Georgia Curry working jobs that offer no insurance:

GEORGIA CURRY: I don’t want to take the risk of not having insurance.

FREDERICA FREYBERG: With salaries that could hardly withstand the high cost of emergency care, buying into the marketplace is the preferred position.

GEORGIA CURRY: Exhale. Hands to the mat. Step back. Take a bow. You earned it.

JUDY WOODRUFF: Later this week, the Obama administration is expected to release its first report of how many people of any age have enrolled in the federal insurance marketplaces so far. The Wall Street Journal today pegged that number at fewer than 50,000.