Hi Lisa_G_2012,
How long ago was this position? If it's within the last ten years or so, see if you can track down the information. It is okay to use years only on your resume, but you might need to fill out application forms that request months for starting and ending dates.
You might be able to figure out the months of employment
from a Social Security earnings report. You can also try to locate old resumes, contact
previous employers, search old records (if available) to see if you have
letters re: start dates or resignation letters, or track down former co-workers
and see if they remember when you started or left.
If the position was from long ago, though, it's probably not a big deal unless you're targeting federal or state positions that require months of employment.
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