The US economy is also a dominant force affecting global capital markets, and in the past five years it has been subject to some unusual influences which are still running their course. There has been a remarkable degree of investment in information technology and communication capacity in the US.
This has been a feature of other countries too, but it was most pronounced in the US, raising the share of overall business investment in GDP to historically high levels in the late 1990s. Expectations about returns to this investment have, until quite recently at least, been very optimistic.