Create a calculated field

Hello everyone,

I have a gallery where the employees who are celebrating their anniversary are displayed.

For this I have a collection:
Set(varCM, Text(Now(),"mm"));
Set(varCY,Text(Year(Now())));

ClearCollect(colWA, Sort(EmployeeDirectory,Mjoined,Ascending));

and then in the gallery I have a filter:

Sort(Filter(colWA,Mjoined=varCM),Djoined,Ascending)

In the gallery I have the fields Mjoined (single line text) and full name, I added one next to the name a calculated field that tell me how many years that employee has been in the company.

Value(varCY)-Value(ThisItem.Yjoined) & " Yrs"

So, I just need is filtering the collection with the employees has one year or more.

How do I do it?

Thank you so much in advance.