Here are polars for Callisto, a Varne 27 with a bermudan rig, 

The codes in the title of the chart indicate what filtering and adjustments have been applied.

S7 means any data points where the wind speed (S) drops by more than 0.7 knots per second are omitted.

A64 means that any data points where the wind direction (A=Angle) changes by more than +6 degrees or -4 degrees per second are omitted. This level of wind angle filtering seems to produce the best curves when the downwash correction is applied.

When a data point is omitted, all the subsequent data points are also omitted, until the boat speed changes. This is because the boat speed data was coming through quite slowly compared to the wind data, and because the boat speed reacts quite slowly to changes in wind speed and direction.

Avg3 means that the speed shown is the average of the top three boat speed values recorded for each wind direction and wind speed

C70D10 means a correction has been made on these results for downwash affecting the wind sensor, which was placed on the quarter of each boat. This is an arbitrary 10 degree (D10) correction at 35 degrees, tapering off to 0 and 70 degrees (C70) using a sin curve. 

No adjustment has been made for the length and sail area/displacement ratios. 

First, with the curves smoothed to follow the high points of the unsmoothed data.

Then with no smoothing

Then both smoothed and unsmoothed curves together for each wind speed.