I keep a spreadsheet of subscription services. Mostly so that I don't forget which ones I am paying. I have a column where I automatically multiply the monthly

I keep a spreadsheet of subscription services. Mostly so that I don't forget which ones I am paying. I have a column where I automatically multiply the monthly cost of a service by 12, so I can see how much it costs me over time. That way I can ask myself whether a $10/month service is giving me $120 a year in value. An improvement to this would be a date for the start of the subscription, and a running tally of how much it's cost in total: was this service worth the $850 it's cost me already?