Reading the legend, it looks like the newer one was obtained under the
US Sailing IMS program which appears to be the
Performance Products Program now on the
US Sailing web site.
I made a jpg so it is easier to see the figures and compare. I also added a picture using the trial version of
Expedition that includes a sample J/30 polar. I captured a screen shot and provided both the
raw text file Expedition uses, and the
file converted to Excel so you can play with it.
I need to get better at using these. Can others post here on how you have used the polars to help your performance?
US Sailing Polar
J/Boats Website Polar Expedition Polar