WASHINGTON (AP) — Maybe you’ve been reading the health care bill in your spare time. Then perhaps you can answer this question:

If Congress makes history and puts a bill on President Barack Obama’s desk by Christmas, how long before the uninsured get medical coverage?

If you said three years or more, you’d be right. Yet many people don’t realize that to keep costs down, lawmakers made compromises that might not appeal to consumers.

“There’s going to be a long period of great expectations and very modest deliveries,” said economist Robert Reischauer, president of the Urban Institute public policy center. That’s assuming Democrats prevail.

Some questions and answers on the House-passed bill and the version the Senate will begin debating in the week ahead; both measures were written by Democrats:

Q: HOW MANY PEOPLE WOULD BE COVERED?

A: The Senate bill would cover 94 percent of eligible Americans under age 65; under the House bill, it’s 96 percent.

That’s a major improvement over the 83 percent now covered, but the safety net would have holes.

Some 16 million eligible people would remain uninsured under the Senate bill and 12 million under the House bill, according to the Congressional Budget Office. That’s not counting illegal immigrants, who would not be eligible for government assistance under either bill.

Both bills would eventually require Americans to get health insurance, or face fines.

Q: Why don’t lawmakers just provide coverage for everyone?

A: Part of the reason is it would cost more, at least $250 billion over 10 years. The president wants to keep the total cost to about $900 billion. But it means workers and their families would be more than twice as likely to be uninsured as older people, virtually all of whom are now covered by Medicare.

Q: How affordable is the new middle-class coverage going to be?

A: It depends.

Most people would remain in their employer plans. Self-employed people and those working in small businesses would be able to buy coverage through a new insurance marketplace, with government subsidies available for many.