Washington Post has a fun article about the Hot Dog Eating Contest in Coney Island here.
This graphic shows various interesting insights about the annual competition:
Joey Chestnut is the recent king of hot-dog eating. Since the late 2000s, he's dominated the competition. He typically chows down over 60 hot dogs in 10 minutes. This is shown by the yellow line. Even at that high level, Chestnut has shown steady growth over time.
The legend tells us that the chart shows the results of all the other competitors. It's pretty clear that few have been able to even get close to Chestnut all these years. Most contestants were able to swallow 30 hot dogs or fewer.
It doesn't appear that the general standard has increased over time.
In 2011, a separate competition for women started. There is also a female champion (Miki Sudo) who has won almost every competition since she started playing.
One strange feature is the lack of competition in the early years. The footnote informs us that the trend is not real - they simply did not keep records of other competitors in early contests.
The only question I can't answer from this chart is the general standard and number of female competitors. The chart designer chooses not to differentiate between male and female contestants, other than the champions. I can understand that. Adding another dimension to the chart is a double-edged sword.
There is even more fun. There is a little video illustrating theories about what kind of human bodies can take in that many hot dogs in a short time. Here is a screen shot of it: