Complex sentence: Participation never exceeded half the estimated work force, and those who contributed typically under-reported income; among the self-employed, evasion rates rose to around two-thirds; the system's finances, nevertheless, remained nearly balanced as late as 1978.
Split into simpler sentences: Participation never exceeded half the estimated work force, and those who contributed typically under-reported income; among the self-employed, evasion rates rose to around two-thirds. The system's finances, nevertheless, remained nearly balanced as late as 1978.