gross_income is used as the basis for most calculations instead of household_income

[anth-volk]

In various places, including standard personal income taxes, spouse deductions, and the social security administration benefit, our R file reference material utilizes a gross_income variable as the basis for calculations. However, this variable is itself added to spouse_income to determine household_income, making it seem as if gross_income is merely the head of household's income, which is unlikely to be the basis for the calculation of most of these programs.