In TRIM3, to be an ABAWD, a person must be non-disabled, aged 18-49, and not in a SNAP unit that contains dependent children under age 18 (program rule CaretakersExemptABAWD controls which persons can be exempt from ABAWD status because of the presence of children). A unit can contain both ABAWDs and non-ABAWDs. For example, if a woman aged 48 is in a two-person unit with a man aged 50, the woman would be an ABAWD, but the man would not. ABAWDs rendered ineligible through failure to meet the work requirement are excluded from the number of people in the unit when determining the unit’s benefit, but the ABAWD’s income is counted in determining eligibility and benefits for the rest of the unit.

Based on estimates of the statewide percentage of ABAWDs exempt from the work requirement, TRIM3 randomly selects ABAWDs to be considered exempt from work requirements. The program rule PercentOfABAWDsExempt indicates what percentage will be considered exempt. By setting this to "1", the user can effectively turn off the ABAWD regulations. For exempt ABAWDs, work status does not need to be checked. All ABAWDs in the same unit are assigned the same exemption status (exempt or non-exempt).

A non-exempt ABAWD can meet the work requirement in a given month in two ways:

1. By working an average of 20 hours per week in that month. Beginning with the 2004 SNAP baseline, an ABAWD is considered to have met the work requirement if MonthlyHoursWorked(month)/WeeksInMonth(month) >= 20. In prior years (before MonthlyHoursWorked was available), this test was approximated as:

   LastHoursPerWeek*MonthlyWeeksWorked(month)/WeeksInMonth(month) >= 20.

2. By earning a weekly amount equal to or greater than what someone would earn by working 30 hours per week at the minimum wage (specified by the program rule MinimumWage). TRIM3 approximates the weekly earnings by dividing the worker’s monthly earned income by the number of weeks in the month. If

   PersonEarnedIncome(month)/WeeksInMonth(month) ≥ MinimumWage * 30

   then the ABAWD fulfills the requirement even if weekly hours are less than 20.

When processing a non-exempt ABAWD, TRIM3 counts the number of months in which the ABAWD’s unit is eligible for SNAP benefits and the ABAWD fails to meet the work requirement. If the ABAWD accumulates three such months before December of the current year, then beginning with the month of unit eligibility following the third month in which the ABAWD failed to meet the work requirement, the ABAWD is denied eligibility in each month until the month following the first month in which he or she meets the work requirement. If the ABAWD subsequently regains eligibility through meeting the work requirement, but then fails to meet the work requirement in a later month in which the unit is eligible, eligibility is continued for that month and the following two consecutive months (assuming the unit is not ineligible for other reasons). Following that, the ABAWD is eligible only if meeting the work requirement (and again, eligibility begins the month following the first month in which he or she meets the work requirement).

The ABAWD rules limit ABAWDs not meeting work requirements to 3 months in a 36-month period. The program rule MethodOfTracking indicates which of three methods of implementing the 36-month clock each state has chosen. The first option simulates a rolling clock, in which the reference period for each month is the preceding 36 months. The second option indicates that the state uses a fixed clock that starts in the first month of participation for the individual ABAWD. After 36 months have elapsed, the clock is reset and the ABAWD goes back to the initial status of having no months to be counted against the time limit. The third option is similar to the second except that the start and reset dates are the same for all ABAWDs in the state. Under the current methodology, the second and third options produce the same results. The program rule MonthsSinceTimeLimitBegan indicates the number of months since time-limiting of ABAWDs began.

Since the effect of the ABAWD regulations spans years (i.e. months that an ABAWD did not meet the work requirements in one year affect how many such months are allowed in following years), TRIM3 needs to make an estimate as to how many such months have been accumulated prior to the simulation year. TRIM3 assumes that the ABAWD’s work status and the ABAWD’s unit’s eligibility in any month of a previous year are the same as in the corresponding month of the current year. However, since not all eligible units actually participate, the program rule PctNotPreviousParticipant specifies the percent of units that TRIM3 should assume did not receive SNAP benefits in previous years even though they are assumed to be eligible. Values of PctNotPreviousParticipant are taken from Alignment Table 10 of the preceding year’s baseline simulation. Using this information, when TRIM3 counts the number of months in which the ABAWD’s unit is eligible for SNAP benefits and the ABAWD fails to meet the work requirement in the current year, it can begin by first taking into account the number of such months from previous years.

ABAWDs who have been excluded from eligibility are not counted in determining the amount of the SNAP benefit that the unit is eligible for. For example, a two-person unit containing an ineligible ABAWD and an eligible ABAWD would receive the benefit calculated for a one-person, rather than a two-person, unit. However, the ineligible ABAWD’s income and deductions are included in the unit’s income and deduction for the purpose of simulating eligibility and calculating the benefit amount. Ineligible ABAWDs are not included in the number of participants in the unit for purposes of determining whether the unit qualifies for a minimum benefit.

Note that TRIM3’s implementation of the ABAWD regulations include a number of simplifying assumptions and approximations:

• ABAWDs are randomly selected for exemption from the work requirement.
• TRIM3 does not model the 15% exemptions authorized under the Balanced Budget Act of 1997.
• ABAWDs can meet the work requirement through work programs and employment and training, but TRIM3 will only give credit based on hours "usually worked per week in the prior year"
• Technically, ABAWDs must be participating in SNAP in order for the first three non-working months to be counted against them, and the three-month extension period must also begin in a participating month. But the TRIM3 approach is based on eligible months, regardless of whether or not the unit ends up participating in those months.
• The work requirement rules for the extension period are slightly different than for the initial period of eligibility, and are not captured by TRIM3.
• States were allowed to count income and assets of ineligible ABAWDs however they chose until federal regulations were issued (in April of 2001). TRIM3 assumes that all of the ineligible ABAWD’s income is counted in determining eligibility for the other members of the unit. The April 2001 regulations state that a pro-rated share is counted. This has not yet been implemented in TRIM3.
• The 36-month "clock" actually started ticking at some point between enactment of PRWORA (August 1996) and the end of November 1996 (the actual timing varied by state). For simplicity, TRIM3 assumes the clock started ticking on December 1, 1996.