OK, I think I have this, though there are a few small details I want to clarify:

(1) The Book data is adjusted by CPI (that is, Book is divided by CPI) and then the WMA is calculated.
(2) The mean (price data) / mean( CPI adjusted WMA book data) should provide multiple to have two lines track
(3) For the variance, are you using close/WMA or close - WMA?
(4) You use the previous 20 years worth of daily data for variance?

Should the closing prices of BRK *also* be adjusted for CPI data? If not, why not? Also, since both lines (the adjusted WMA and the closing prices of BRK) exhibit linear or even exponential trends, should we be taking the log of both of the data and removing the linear part of the log line on each and then comparing the variance from the line?

Thanks, G.