Trying to create a new date based on an existing date minus 12 months.

mike.thorpe17421

I have an existing date column [First Commercial Sales Date (Best Case)] and want a new date to be create minus 12 months.

i.e. The [First Commercial Sales Date (Best Case)] date is 22/11/2025 (22 November 2025) and the new date (minus 12 months) should be 22/11/2024 (22 November 2024).

Can anybody help?

Thanks

Andrée Starå

Hi @mike.thorpe17421

I hope you're well and safe!

Try something like this.

=
DATE(YEAR([First Commercial Sales Date (Best Case)]@row) - 1, 
MONTH([First Commercial Sales Date (Best Case)]@row), 
DAY([First Commercial Sales Date (Best Case)]@row))

Did that work/help?

I hope that helps!

Be safe and have a fantastic week!

Best,

Andrée Starå | Workflow Consultant / CEO @ WORK BOLD

✅Did my post(s) help or answer your question or solve your problem? Please support the Community by marking it Insightful/Vote Up or/and as the accepted answer. It will make it easier for others to find a solution or help to answer!

mike.thorpe17421

That is perfect thanks Andrée Starå. Another question, if I wanted to change the period to 18 months or 24 months what would be the changes to the formula?

Andrée Starå

Hi @mike.thorpe17421

I hope you're well and safe!

Try something like this.

=
DATE(YEAR([First Commercial Sales Date (Best Case)]@row) - 1, 
MONTH([First Commercial Sales Date (Best Case)]@row), 
DAY([First Commercial Sales Date (Best Case)]@row))

Did that work/help?

I hope that helps!

Be safe and have a fantastic week!

Best,

Andrée Starå | Workflow Consultant / CEO @ WORK BOLD

✅Did my post(s) help or answer your question or solve your problem? Please support the Community by marking it Insightful/Vote Up or/and as the accepted answer. It will make it easier for others to find a solution or help to answer!

mike.thorpe17421

That is perfect thanks Andrée Starå. Another question, if I wanted to change the period to 18 months or 24 months what would be the changes to the formula?

mike.thorpe17421

https://community.smartsheet.com/discussion/comment/331487#Comment_331487

Immediate response Andree, thank you so much.

mike.thorpe17421

Hi Andrée Starå. As mentioned above, I have another question, if I wanted to change the period to 18 months or 24 months what would be the changes to the formula?

Any help much appreciated.

Kind regards

Mike