Hi Chris, B28002_001 would be the total number of households (with or without an internet subscription). This is useful as a denominator for creating percentages with the other indicators. 002 is households with any kind of internet subscription. The sum of 002, 012 (internet without a subscription), and 013 (no internet) should equal 001. Most ACS tables will begin with an indicator of the total universe (all households, people, etc.) described in the table, so many 001 indicators from different tables will be the same.
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