Group by date and create new field in Pivot Table

[Smally]

Hi, I've got a table with various fields, one of them is named Date and contains dates from 01/01/2010 upwards.

I have a pivot table, and I've somehow managed to stick the Date field in the Report Filter and create a new field only shown in the PivotTable called Years.
My question is, how did I do this?

I've had to change my source table. I added a field called DateTo, and change the existing Date field to DateFrom. But when I refreshed the pivot table, the Years field disappeared.

I remember Excel not letting me group dates in the Report Filter section, so I put it in the Row Labels section, grouped by years, then moved it to Report Filter and inserted a Splicer so I can filter the Pivot Table by the years. I've re-done this with the new DateFrom field, but Excel has not created a new field called years. Am I doing something incorrectly?

[Pepe Le Mokko]

Grouping will not work if one or more records are empty or if dates are not real dates but text looking like dates. Impossible to say without seeing the sheet

[Smally]

All records have a date entered, and are valid dates.

The grouping works, I just have no idea how I managed to create a new field within pivot table that states Years.

What I'm thinking is, if I can make this Years field again, I won't have to do the strange workaround technique of putting Date into the Row Labels section, grouping by years, then moving Date to Report Filter