Fully insured = 40 credits; a worker can earn up to 4 credits a year.

Disability: expected to last 12+ months or end in death; 5-month waiting period; under 24 needs 6 credits in the last 3 years.

Survivors: currently insured = 6 credits in the last 13 quarters; lump-sum death payment is $255.

Full retirement age 67 (born 1960 or later); earliest 62, reduced.