I am currently downloading ASEC household income data for a large number of years (1969 to 2021). I am only interested in a few income variables, but there are a total of ten pre-selected variables out of which I only need three (YEAR, SERIAL, ASECWTH).
The extra seven pre-selected variables make the download file much larger than necessary but I cannot remove them - when I uncheck them in my cart, they still appear in the downloaded file.
How can I remove these pre-selected variables from my data cart?
You cannot avoid including pre-selected variables from the variable topic list view (e.g., the demographic variables list), but you can remove them from your extract when viewing the “Data Cart” summary page, which summarizes the full contents of your extract before you click on “Create Data Extract” (see first screenshot below). When you get to this data cart screen, simply click on the check-marks next to the variables you would like to omit to deselect them; you can see that I have deselected YEAR in the first screenshot below. When you advance to the extract request summary page and click on “show” in the variables row, the variables you removed at the data cart step should NOT be included any longer (you can see that YEAR is not included in the second screenshot below). Note that if you navigate back to add additional variables after this stage (or revise your extract), you will need to remove these preselected variables from the “Data Cart” summary page again before submitting your extract.
Deselect variables you do not want included when viewing your data cart (here I have deselected YEAR):
Confirm they have been removed by showing the variables included from the data extract summary page (you can see YEAR is not listed):
Many thanks @KariWilliams for this detailed and informative answer!