Can anyone think of a simple way to accomplish this:

Goal - use the Linest function to create a regression against a series
of dynamic ranges.

Example:

Column A Column B Column C
Row 1 DATE DOW VALUES

1/1/08 =weekday(A2) V1
. . .
. . .
. . .
12/31/08 . .


Using the Linest function, I'd like to create a regression that looks
at

n # of rows back (so flexible enough to include all data or from this
point in time to a limited number of days/weeks back)


Tuesdays Values = F ( Prior Monday, Prior Sunday, Prior Saturday,
Prior Friday, Prior Thur, Prior Wed, Prior Tues)

I understand the linest function and how to use Index to find all the
coefficients, rsquared, errors, etc. so no worries there.
But how can I create the ranges that pull the data that select only
data from a particular day of the week. Yes I know I could
take lots of real estate and repeat the values across multiple
columns. But that seems like such a waste since the values already
exist.

Any thoughts to this puzzle?