MARGINAL DEDUCTION RATES
148. The Treasury defines the poverty trap as
occurring "when those in work have limited incentives to
move up the earnings ladder because it may leave them little better
off".[375] Marginal
deduction rates are used to measure how far people's incentives
to increase their income are being reduced. For instance, a marginal
deduction rate of 70% means that, for every one pound of additional
gross income, 70 pence of that extra pound is taken away, either
by taxes or a reduction in benefits.
149. The Government has stated that "as
a result of the introduction of tax credits, in combination with
other reforms, individuals have improved incentives to progress
in work".[376]
The Treasury told us that "to help make work pay, the Government
has also reduced the number of families facing the highest marginal
deduction rates (above 70%) by over half a million since 1997".[377]
As can be seen from Table 4, the Government has sharply reduced
the number of working families with the highest marginal deduction
rates of over 90%, from 130,000 before the 1998 Budget to 25,000.
Table 4: Number of working heads of non-pensioner
families with high marginal deduction rates: changes since 1997