Is there a word to make the distinction between a Year/Month Combination and a Month

Is there a word/phrase that would distinguish the combination of a year and month from a month?

I'd call "January" a month

I'd call "January 2011" a ____?

January is (the name of) a month

January 2011 is (the name of) a (specific) calendar month.

January is a month.

January 2011 is a month of a year, or a month and a year. (It is not a year and a month; a year and a month is a duration.)

January 31, 2011 is a date.

I can't think of any way other than that to name the month-and-year combination.

I meet this problem desigining Business Intelligence applications. Objects that combine the Year and Month often simplify business rules.

For example

Year-Month between 2010-03 and 2011-02

(a rolling year) is a lot easier for a business user to create/understand than

(Year = 2010 and month >-03) or (Year = 2011 and month <= 02)

I call such an object a 'Year-Month' : clumsy maybe, but self-descriptive.