Chart: How Serena stacks up against the other Open Era Slam leaders

Serena Williams defeated Caroline Wozniacki in the women's final of the U.S. Open on Sunday, her 18th career Grand Slam title.

The win puts Serena, 32, in rare company -- she's now tied with Chris Evert and Martina Navratilova for second all-time in women's singles Grand Slam titles in the Open Era. Steffi Graf leads with 22*.

How is Serena tracking in comparison to those three? The chart below compares the four champions and tracks their ages at each step of the way.

Here are a few pertinent takeaways:

-- Only one Slam on the list was won by someone older than Serena is now. That would be Navratilova's 18th and final Slam win at Wimbledon in 1990. Navratilova made two more Slam finals, including one in 1994, when she was 37.

-- Serena has had the widest spread of the group from first to last. She was 17 when she won her first Slam, a 15-year gap from No. 1 to No. 18. Graf got all 22 of hers in between ages 17 and 29. For Evert, the bookends were 19 and 31. For Navratilova, 21 and 33.

-- Though Serena won her first well before Evert and Navratilova, both caught up to her in the age race. Evert was faster to every title from No. 7 on. Navratilova was five years slower than Serena to No. 3, but was younger than Serena for Nos. 14-17.

-- Interestingly, all four players won their first and last at the same venue. For Graf and Evert, it was the French Open. For Navratilova, Wimbledon. For Serena, the U.S. Open, though obviously she could still add to the list.

-- Evert won the most French Opens among the four, with seven. Navratilova owned Wimbledon, winning it nine times. Evert and Serena each have six U.S. Open titles. Serena has the most Australian Open titles (five), though the other three on this list skipped that tournament several times.