These results, however, hide a clear difference between the two subperiods: the GDP
response is much stronger in S1. As panel E of Table 6 shows, in S1, at 1 year the response
is significantly positive in all countries except Australia, although it is large only in the
US; at 3 years, it is significantly positive in the US, Canada and Australia. In S2, at 1
year it is significantly positive, but small, only in Germany and Australia; at 3 years, it
is significantly positive only in Australia, about 0 in the US, and significantly negative
in Germany, the UK and Canada, between -1.2 and -2.2. Thus, except in Australia and
Germany at 1 year, where the difference is essentially 0, the cumulative GDP response
is always smaller in S2, and always significantly so. Note also that the GDP response
estimated for the US tends to be larger - and in most cases considerably so - than in all
the other countries.
Are these differences, both across countries and across periods, due to underlying
differences in the government spending processes? As we have seen, the government
spending response is less persistent in S2 in the US and the UK, two countries with a
large drop in the GDP response in S2. The cumulative cyclically adjusted multiplier34
expresses the cumulative change in GDP per each cumulative change in cyclically adjusted
government spending equal to one percentage point of GDP. As panel F of Table 6 shows,
it displays much the same pattern across subperiods as cumulative GDP, although the
standard errors are somewhat larger.
These differences are also unlikely to be due to underlying differences in the responses
of net taxes: as we have seen, in S2 discretionary taxes usually fall, or increase less than
in S1.