20.5 How do countries compare?
The USA is currently the strongest swimming nation and that can be measured in a variety of ways. Instead of looking at that, consider the strengths of nations across the same events for men and women. Figure 20.12 plots the number of female swimmers of a country in the top 200 for an event against the number of male swimmers of that country in the same event. The graphs are shown for the nine countries with the most swimmers in all amongst the 200 best times for the 17 events for men and women.
Figure 20.12: Numbers of female swimmers in the top 200 plotted against numbers of male swimmers in the top 200 for each of 17 events by country (the dashed lines represent equality)
The USA, Canada, and China have more female swimmers than male swimmers in the respective top 200’s in all events. Russia has more men than women in the top 200 lists in all events.
Answers Freestyle is fastest, then butterfly, backstroke, breaststroke. Backstroke catches up on butterfly over longer distances. The 200th fastest man is faster than the fastest woman in all four strokes. After full body swimsuits were banned it took several years to get near to the earlier records again.
Further questions How do the performances of individual swimmers develop over time? What effect do turns have on swimming performance? Comparing times over different pool lengths could be used to study the effect.