If you are looking to format the date that certain way on the printed report, perhaps just change the format rather than use a formula?

- Put the Date field onto your report
- Right-click and choose Format Fields
- Go to the Date/Time screen and at the bottom, click Customize.

You'll get into a screen where you have full control over how dates print.

- Change the order to YMD
- Select None for day to not print the day
- Use a space for the first separator instead of /
- Delete the second separator
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I'm surprised you're not getting errors with your formula because the Year function outputs a number, not a string. Perhaps use ToText(Year(Date),0) to remove decimals?