Across the board, women's records stand at about 90 percent of men's. There's some variation there, but not too much: among these races, the women's records all fall within 1.8% of each other.

2. The fastest woman swims about as fast as the fastest man did -- during the Johnson administration. In freestyle, the women's world record time is as fast as the men's time was in 1968. In butterfly, the fastest woman swims as fast as the fastest 1967 man (Mark Spitz FWIW). And in backstroke, the magic male-female intersection is, again, 1967.

The only 100m aquatic record that doesn't fall during that period is the breast stroke, where Jessica Hardy meets the 1972 men's record of one minute, 4.9 seconds. (And, in fact, female swimmer Rebecca Soni eclipsed that time before Hardy did.)

3. But women's records have been closer to men's records in the past.

Florence Griffith-Joyner holds the current women's 100m dash world record time, at 10.49 seconds. She set it in 1988. Since then, no one (who hasn't admitted to doping) has challenged it:

In the above graph, look at how close Joyner got to the men's record at the time. In August 1988, when she set her record, she ran at about 95% of where the men's record stood.

4. But Joyner's record -- the fastest female 100m dash in history -- is only as fast as the men's record was in the Harding administration. Despite the fact that Joyner got within 5% of the contemporaneous men's record, she only ties men who ran seventy years before. Her record of 10.49 seconds was surpassed by the American Charlie Paddock, with a time of 10.4 seconds, on April 23, 1921.

5. Over the past century, women's times have improved much more than men's have. Another cool thing about the graph above? See how the women's time quickly shakes out, from what the fastest women with access to the Olympics could run to the time that much more closely aligns with what's possible for the fastest woman. That quick drop -- that's the entire sports training societal complex reorienting itself, becoming more socially egalitarian (and economically successful) by turning its attention not just to talented boys, but to talented girls. The same hastily meandering movement downward is present across contests, like, for example, in this graph of women's 100m freestyle performance.

It stands to reason that, as societal structures improve even further, women's records could continue to improve as well.

6. In swimming, certain strokes seem better suited to women. Decade on decade, women are better able to close the gap with men in the backstroke and freestyle.

7. And generally, very long races seem to benefit women. Looking at the table above, of men's and women's records across a range of different races, women come closest to men's records on races that depend on aerobic strength: the open water swim and the marathon.