1. 1 An introduction to the problem This book deals with the
development of public pension schemes. The operation of public pension
schemes has drawn a great deal of attention recently due to ageing of
the population which has become apparent since the 19 70s. This would
probably have been less of a problem if these schemes had been financed
by a Capital Reserve (abbreviated from now on as CR) system. As is
well-known, in a pure CR-system individuals (or generations) save for
their own retirement. The (average) rate of return on the premiums paid
in this system equals the real rate of interest and, in principle,
changes in the rate of population growth do not affect the premium rate
or the benefit rate of the system. Most public pension schemes, however,
are financed by a Pay-As-You-Go (abbreviated from now on as PAYG)
system. In this system current pension payments are financed by current
premium payments. In contrast to the CR-system intergenerational
transfers occur in this system. If the number of retired people
increases relative to the number of workers the premium rate will
increase under PAYG. In itself this increase does not have to imply any
concern for the premium paying population. What counts is whether the
rate of return under a PAYG-system will fall (too far) below the rate of
return the CR-system is offering.