I would certainly store the results of the formulae in a history table at the very least. Whether you need to store the formulae themselves or not depends on how many formulae you have and how they vary. Your basic table might look something like this
calculation_id
record_id
points
formula_ref
If you have, say, 6 fixed formulae of which the active formulae are some combination of these then your "formula_ref" might be a unique string per formula (i.e. "first10"). If your formulae vary more than that, or the values vary (i.e. "first x" might change from "first 5" to "first 10" etc) then you might need a separate table for the formula combinations and link to them from the history table using a foreign key. The same goes if you need to allow dynamic adding/editing of the formulae from the app (via an admin GUI or similar) as opposed to manual changes in the code.
Your schema will also depending on how you intend to use the data. If you are only ever interested in the history per record, the basic schema as above with a text based formula_ref field would probably suffice (with an index on the record_id).
Feel free to post back your specific schema plan for more comment...