Calculates the main statistics of a linear regression: the slope and
intercept of the line, the coefficient of determination, also known as r-square,
the standard error of the slope, and the p-value for the regression. This
function takes two equal-length sequences of raw data. Note that the dependent
variable, as always, comes first in the argument list.

You should first look at your data with a scatter plot to see if a linear model
is plausible. See the manual for a fuller explanation of linear regression
statistics.