Movies in the wrong year

I have iMovie 10.0.9 (Yosemite)

I have some clips I recorded on a rental camera with the wrong date while on vacation. These clips show up in the 2012 folder and I want to change the date on them or move them to the 2015 folder. I have read what is available in the community but none of the drop down menus offer the solutions suggested. How do I move or change the dates on them? Thanks!