Once upon a time, U.S. figure skating was incredibly popular.

The sport used to produce instantly recognizable names like Michelle Kwan, Kristi Yamaguchi and Tara Lipinski.

And who could forget Tonya Harding and Nancy Kerrigan? The pair made headlines and fueled intrigue in the sport, for the wrong reasons.

In January 1994, a month before the start of the Lillehammer, Norway Olympics, Harding's main rival, Kerrigan, was struck on the knee with a baton. Harding's husband was part of a plot, and he spent two years in prison for the crime as part of a plea deal. Kerrigan recovered in time for the performance and went on to take silver.

Unsurprisingly, the ladies' short program that featured both Harding and Kerrigan remains the highest-rated Winter Olympic programming of all time.

In 1994, it was the sixth-highest rated program in TV history with 48.5 million viewers. At the time, it was the third-highest rated sporting event behind Super Bowl XVI and Super Bowl XVII.

Given the drama that surrounded it, that figure skating viewership milestone would be hard to rival under the best circumstances, much less during a ratings retreat.

But while Super Bowls in the current era routinely surpass 100 million viewers, figure skating failed to keep pace with even the popularity it had in the '90s.

In 2014, during the Games in Sochi, there were 11 days of figure skating competitions broadcast in prime time. They netted 21.4 million viewers -- less than half the viewers who tuned in for the Harding and Kerrigan segment.

The drop has also been noticeable in the viewership numbers for the U.S. Figure Skating Championships, which are used to help determine who will compete for Team USA during Olympic years.

The ladies' free skate competition is the most popular event. Data is limited from that time, but the 1998 U.S. Figure Skating Championships brought in at least 6.8 million viewers. That same event in 2018 drew 4.5 million viewers.

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Former figure skater and analyst Dick Button blames the drop in popularity on the sport's complicated scoring system.

Figure skating used to be judged with a 6.0 system. But shortly after a judging scandal during the 2002 Salt Lake City, Utah Winter Olympics, the International Judging System was put in place.

The newer system doesn't have a defined highest score. Instead it uses a complicated point system that can allow skaters to earn hundreds of points and "personal bests."

"The old 6 point system was understandable and one could hear folks in a bar cheer and argue about whether someone should have had a 5.7 or 5.8," Button said. "Now a 'personal best' of 283.4 points is confusing!"

Button said the new scoring system rewards people even if they make mistakes or fall during their routines.

"If you do a quad and fall down, you still get points for it -- can you explain that to me?" Button said.

Another big difficulty the sport has faced is a dearth of stars.

"I miss the personalities, all of whom were different," Button said. "Where are the Katarina Witts? The Dorothy Hamills?"

The last mainstream stars on the women's side were Michelle Kwan and Tara Lipinski who competed in the 1998 Olympics. On the men's it was Johnny Weir who gained fame as much for his personality as his performance on the ice. He made it the 2006 Olympics and came in fifth.

Breakout performances from U.S. skaters could help turn things around at least a little.

Skaters like Mirai Nagasu, 24, might be primed to do that.

On Monday, Nagasu became the first American woman to land a triple axel in Olympic competition. Her performance helped Team USA win its second straight bronze medal in the figure skating team event.

Only two other women, both from Japan, have accomplished the feat at the Olympics, and only two other Americans have completed the triple axel in competition. (Harding was the first to do so in 1991 at the U.S. Championships.)

The ratings from Nagasu's event hit a peak of 29.7 million viewers. That's approaching the 32.7 million who tuned in to watch Michael Phelps' last race during the Rio Olympics.

Figure skating viewership is at its peak during the Olympics, which means it's the best chance for a star to emerge and for the sport to remain in the public's consciousness.

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While it may never reach the status it enjoyed in the '90s, there is some good news for figure skating's future.

Viewership of the U.S. Figure Skating Championships did increase this year. The broadcast of the ladies' free skate climbed 50% in ratings and 60% in viewership over 2017.

The championships were also the highest-rated and most-watched since 2010. That includes numbers from 2014 -- the last time the championships led into the Olympics.

In order to produce figure skating stars, you need more interest and participation in the sport. There's good news on that front, too.

Membership in the U.S. Figure Skating organization is growing again. It's up for the fourth year in a row. It reached its peak during 2005 when it surpassed 196,000. That was also Michelle Kwan's last season.

Another boost is likely coming from the fact that the Harding-Kerrigan scandal was back in the news ahead of Pyeongchang thanks to the release of the highly acclaimed movie "I, Tonya."

The film has raked in over $25 million in North America since it was first released in December.