ACS data download at zip code level

I was looking to download the number of housing units per zip code for certain US cities/counties. I followed the instructions given by Peter regarding the ZCTA data available on the US census site. I entered "Housing Units" as my topic for San Diego County and downloaded the table called "Profile of General Population and Housing Characteristics: 2010" that resulted from the query. However, the file has more than 33,000 rows and the second column which I assume to be the zip codes ("Geo.id2") starts at 601 and goes all the way to 99929. The top row has "Geo.id2" as 6073 and lists the Geography as San Diego County. The total population and total # of households seem right. But I am not sure how to interpret all the data below it. I would greatly appreciate any help in understanding this data!

Thank you!
Gunjan

I was looking to download the number of housing units per zip code for certain US cities/counties. I followed the instructions given by Peter regarding the ZCTA data available on the US census site. I entered "Housing Units" as my topic for San Diego County and downloaded the table called "Profile of General Population and Housing Characteristics: 2010" that resulted from the query. However, the file has more than 33,000 rows and the second column which I assume to be the zip codes ("Geo.id2") starts at 601 and goes all the way to 99929. The top row has "Geo.id2" as 6073 and lists the Geography as San Diego County. The total population and total # of households seem right. But I am not sure how to interpret all the data below it. I would greatly appreciate any help in understanding this data!

Thank you!
Gunjan