Kentucky Fried Chicken, Coca-Cola, etc. have secret trade formulas. Is
there a way to securely hide a secret formula?
I want to create a function (macro) that when applied to a particular
cell will compute a value based on variable elements of a spreadsheet
as multiplied by undisclosed fixed elements.

Example: Assume a1,b1, c1 and d1 have variables. Also assume that the
fixed elements are fe1=.4,fe2=.25,fe3=.11,fe4=.24 stored in the
function I created called rating.

Thus, cell e1 =(function) rating(a1,b1,c1,d1) and yields the result of
(a1*fe1)+(b1*fe2)+(c1*fe3)+(d1*4).

Is there a way to hide the declaration of a function or must the
function be declared in another language where it MIGHT be more
secure? The use of another language would seem to raise issues like
impact on speed.

Is it possible to create the function and disable macros to conceal
the process to all but the most knowledgeable Excel users?

A newbie at writing macros, any help provided will be appreciated...