Array columns vs normalized table

I work with state labor data which is reported to us in the form

    industry, year, quarter1, quarter2, quarter3, quarter4

where each quarter represents an employment count. Obviously, this can
be normalized to

    industry, year, quarter, employment

Can anyone comment on, or point to me to an article or discussion
regarding, why one would use an array column instead of normalizing
the data? That is, would there be any benefit to storing it as

    industry int, year smallint, employment int[ ]

where the last column would be a four element array with data for the
four quarters.

Thanks,
--Lee

--
Lee Hachadoorian
PhD Student, Geography
Program in Earth & Environmental Sciences
CUNY Graduate Center