What commands would I specifically type into Microsoft's Excel to
create a macro in an Excel spreadsheet that would take time series
data in a column and create a parabolic extrapolation of the
underlying data? For example, it is a given that I know the monthly
high of a stock looking back one year, and the most recent lowest low,
now extrapolate the symmetrical mirror image of the underlying
parabolic as drawn from given high to low. Linear regression and
straight line answers are not wanted here. Looking for conic sections
and curve linear answers!