insert a column with the last year of dates in it. This can be adjusted to any contiguous period but must be specified relative to the present.

magic.sql

insert into myschema.mytable

with ten_numbers as (select 1 as num union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9 union select 0)
,generted_numbers AS
(
    SELECT (1000*t1.num) + (100*t2.num) + (10*t3.num) + t4.num-5000 as gen_num
    FROM ten_numbers AS t1
      JOIN ten_numbers AS t2 ON 1 = 1
      JOIN ten_numbers AS t3 ON 1 = 1
      JOIN ten_numbers AS t4 ON 1 = 1
)
select  (getdate()::date - gen_num)::date from generted_numbers
where gen_num between 0 and 365
order by 1;