TRI-STATE - Charity Ringquist expected her ninth birthday to be a lot like any other day. She planned to rise early today, cook breakfast and see her 6- and 8-year-old daughters off to school.

Once her husband left for work, she would turn her attention to her 2-year old while juggling housekeeping chores. Later, the plan was to run to the grocery store in between taking the two oldest girls to gymnastics and tae kwon do.

Ringquist's day is not an imaginative round of "playing house."

Today is Feb. 29, or Leap Day, which comes around once every four years.

And so, although she turns 36, today is only the ninth time that Ringquist has been able to observe her birthday on the date she was born in 1972.

She is a "leaper," one of a relatively rare group of people born on Feb. 29.

"Even when you didn't have the 29th, we still celebrated on the 28th. We still did something every year," she said.

Feb. 29 is added to the calendar every four years to keep the calendar consistent with the earth's journey around the sun. According to Honor Society of Leap Year Day Babies, with a Web site at www.leapyearday.com, only 0.0684 percent of the world's population, and about 200,000 Americans, are born on a leap year day.

Ringquist said it took her a while as a child to understand what was unusual about her birthday.

"I've known my birthday was (on leap year day) pretty much as far back as I can remember. Mom would always tell me, 'Every four years, you have an actual birthday,'" she said. "When the 29th came, she would be like, 'This is a REAL birthday for you.'"

Ringquist said that, on occasion, having a leap year birthday has created some obstacles. For example, sometimes official agencies and computer systems have not recognized her Feb. 29 birthday.

"I had some trouble one time in college. The computer system kicked (my birthday) out. There was no 29 when I tried to scroll down to it. Sometimes I've just had to put the 28th," she said.

Overall, she said, it is "kind of special" having a leap year day birthday.

"If you have a birthday every year, it's just like, a regular thing. I guess it's a little special because it only comes every four years," Ringquist said.

Denise Brining of Williamsport has a standout leap year day birthday this year. Brining, who was born in 1968, is celebrating her birthday on its actual date for only the 10th time.

Her daughter, Samantha, celebrated her 10th birthday Feb. 15.

"I think it's pretty cool. My friends say it's unbelievable. I have to explain it to them, then they get it," said fourth-grader Samantha, who goes by "Sami."

Denise Brining said Sami's friends like to joke about it.

"They think it's neat because I'm the same age as them. They'll tease and say, 'I'm older than you!'" she said.

Denise Brining said that while getting older does not really bother her, she does enjoy ribbing her friends about her leap year "youth."

"Sometimes, when my friends turn 30 or 40 they'll get upset, but not me. Of course, I can say, 'Well I'm only 10,' or whatever it is that year," she said.

Brining said she has known of only one other person with a leap year day birthday.

"I really like it because it's unusual. I get to stay young and it's memorable," Brining said.

Sonja Mundey of Clear Spring, a leap year baby who turns 64 today, is looking forward to celebrating her "16th" birthday. Mundey said her granddaughter, Lindsey Trumpower, is 16.

"This is the only time in our lives she and I will be the same age," Mundey said.

The Web site www.leapyearday.com offers an "honor roll" of leap year day birthdays, a news magazine called "LEAPzine" and links to unique gifts for "leapers."