(a) General. If you pay your pro rata share toward monthly household operating expenses, you are living in your own household and are not receiving in-kind support and maintenance from anyone else in the household. The one-third reduction, therefore, does not apply to you. (If you are receiving shelter from someone outside the household, we value it under the rule in § 416.1140.)

(b) How we determine a pro rata share. Your pro rata share of household operating expenses is the average monthly household operating expenses (based on a reasonable estimate if exact figures are not available) divided by the number of people in the household, regardless of age.

(c) Household operating expenses are the household's total monthly expenditures for rent, mortgage, property taxes, heating fuel, gas, electricity, water, sewerage, and garbage collection service. (The term does not include the cost of these items if someone outside the household pays for them.) Generally, we average household operating expenses over the past 12 months to determine a pro rata share.