Click here to see the SAS code. 
Click here to see the example.

This is a sas enhanced version of the following WindRose chart
http://www.originlab.com/index.aspx?s=9&lm=+152&pid=761

By putting a 'donut hole' in the center, rather than starting
each windrose bar/arm at the infinitely small center point,
you are able to much more clearly see the inner-most bar/arm
segments (in the original chart, they are not distinguishable
at all).

Instead of having my bars/arm spread out wider at the
ends, I keep mine a consistent width the entire length of the
bar/arm.  This helps avoid "area size bias".

Also, rather than putting the scale out to the size (which is a
little difficult to line up which number goes with which 
concentric circle, I put labels on the actual concentric circles.

In addition to the windrose chart, I also include a table (scroll
down below the chart) of the actual values.  I sum the rows and
columns, so you can see the totals any way you want.

One note - I couldn't read the small/original chart text well enough
to be certain whether wind speed was kph or mph -- I decided to 
call it mph (I might be wrong, but it's just a proof-of-concept
example :)

The code approach:

I did not use the new v9.2 sas/graph windrose for this chart.
Instead, I used custom annotate.
The concentric circles are annotated 'pies'.
The arms (bars) are annotated lines (using 'move' and 'draw').
And the legend is annotated text 'labels'.

---

And here is some info summarized from the Originlab page (see link
above) describing this particular windrose chart...

"Windroses are used to present wind speed data and wind direction data 
that has been collected over some time, so that the dominant wind pattern 
for a particular area can be determined. [...]
The length of each "arm" is proportional to the fractional frequency at 
which that windspeed (and below) was observed from that direction. 
Different colours on each "arm" indicate the windspeed. 
For example, most winds came from the south to south-west, 
but winds with higher windspeeds came from the west."


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