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?