Returns with adjusted gross income can be both taxable and non-taxable. Returns with no adjusted gross income are non-taxable. Adjusted gross income means gross income minus a series of allowable deductions (e.g. trade and business deductions, expenses of travel and lodging in connection with employment, losses from sales or exchanges of property, etc.) Should these allowable deductions exceed the gross income, there is an adjusted gross deficit.
1917-1928, 1943 and 1945-1954: Returns with no net income (1917-1928, and 1943) or no adjusted gross income (1945-1954) were not included in the state totals, but were in the national aggregate. Why? According to the IRS, returns with adjusted gross deficit were too few and the sample variability too great, to permit their presentation on a state basis. For consistency purposes, I subtracted them from the national aggregate for both variables: number of returns and income amount. 49
1913-1916: No net income data are available at the state level. Income brackets start at [$3,000 - $4,000) except for 1913, with [$2,000 - $3,333.33) being the lowest income class.
1946-1952: Non-taxable returns of AGI of $4,000 and over are all included in the [$4,000 - 5,000) income class.
1943 and 1945: Non-taxable returns of AGI of $1,000 and over are all included in the [$1,000 - 2,000) income class.
1942: The 1942 table does not detail Forms 1040A by income classes and displays the state aggregate only. Therefore, the 1040A forms cannot be used for the calculation of fractiles, even though their value appears in the state totals.
From 1943 on, money amounts for net income (1943) and AGI (1944-2003) are in $1,000.
1962: Delaware data appear in the national aggregate, but not separately.
The operation is a substraction for the number of returns, but an addition for income amounts, as a deficit is a negative number.