Question Enter a Date and it will deduct 1

[mister_T]

Good Day,

I'm creating s simple database to track my printer toner supplies, what i want is that..every time I select a date (using date picker) it will automatically deduct 1 from the total number of toners on stock. Right now, i have to input 1 in a field and it will update the remaining toners.

any help is greatly appreciated. thank you.

 

[Anakardian]

If you only ever use a single toner on each occasion you count count the number of dates recorded and subtract it from the total number of toners ever bought.
If you use more than 1 toner you need to either make two records of use the field you are currently using.
If you do not want to change your fields you could set the default value of the field to 1. That way you don't need to enter anything.