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prev_year 

        # Date.prev_year

(from ruby core)
---
    d.prev_year([n=1])  ->  date

---

This method is equivalent to d << (n * 12).

    Date.new(2001,2,3).prev_year      #=> #<Date: 2000-02-03 ...>
    Date.new(2008,2,29).prev_year     #=> #<Date: 2007-02-28 ...>
    Date.new(2008,2,29).prev_year(4)  #=> #<Date: 2004-02-29 ...>

See also Date#<<.

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