Tracking credit card points

[AC]

I've decided to start tracking my points on my cards because the monthly
statements do a poor job of  showing me the activity.  For this
application, is it better to set up the point tracking account as a
stock-type account or a currency?  The value when redeemed fluctuates
but I will always know how many points were redeemed (an integer number)
and the total dollar value that is being converted (e.g. I will know I
spent 1830 points on a purchase that would have totaled $23.95 today but
it may not be that same total tomorrow).

The only thing I don't want to have happen is for the system to see this
new tracking as some kind of value adjacent to my actual stock accounts
to include in reports.  For convenience it should live within the same
file but behave as an independent entity.