Beginning hypothesis: Was the real reason for the Great Depression, convergence?

Here is real GDP since 1870 and there is not any evidence of for convergence in production in the US. THe average long term growth rate has not changed in over a hundred years. http://www.visualizingeconomics.com/2010/11/04/log...

Looking for evidence of

income convergence among

the world’s nations has

become a fashionable pursuit.

Far from narrowing, the gap

between the incomes of the

rich and poor countries has

grown markedly and is likely

to widen further.

ONVERGENCE—the tendency for

poorer countries to grow faster

than richer ones and, hence, for

their levels of income to converge—

has recently received a great deal of

attention in the economics literature. Along

with “globalization” and “competitiveness,”

the theme of “convergence” has spilled over

into public discussions of policies and

prospects for developing countries. Well,

forget convergence—the overwhelming feature

of modern economic history is a massive

divergence in per capita incomes

between rich and poor countries, a gap

which is continuing to grow today.

Moreover, unless the future is different in

important ways from the recent past, we

can expect this gap to grow ever wider.

Divergence past

The very feature that marks the beginning

of modern economic history also

implies a major increase in the difference in

per capita incomes across nations. Call it

the industrial revolution, the emergence of

modern capitalism, or the take-off into sustained

growth, at some point in the late

nineteenth century the annual growth rates

of the now-rich industrial countries accelerated

from historically low levels (0.5 percent

or less), to 1–2 percent per year. The

fact that this acceleration was not universal,

or even widespread, implies that the

gap between rich and poor countries’

growth rates widened and the gulf between

their per capita incomes—which was probably

already wide—began to grow.

Given different exchange rates and different

mixes of tradable and nontradable

goods among countries, how can we compare

income levels? We can compare them

by using purchasing-power-adjusted measures

of income. One important feature of

this adjustment of incomes is to account for

the relative cheapness of nontradables in

poorer countries. Using a purchasingpower-

parity measure substantially raises

the estimate of income of poor countries relative

to their income expressed in US dollars

at official exchange rates—typically by

a factor of 3 to 5, depending on particular

countries’ prices.

Measured in purchasing-power-parity

terms at 1985 prices (P$), the ratio of the

per capita income of the richest country

(the United States) to the average per capita

income of the poorest countries grew from

around 9 (P$2,181 compared with P$250) in

1870 to over 50 (P$16,779 compared with

P$325) in 1960. In absolute terms, the

income gap between countries grew even

more, expanding more than eightfold over

this period. The average absolute difference

between the income of the richest country

and the incomes of all others was about

P$1,500 in 1870 but, by 1960, this gap had

If you aren't having any luck looking for commodities/durables in general, you might try looking up specific commodities etc or look at production numbers by specific manufacturers.

Also, rather than just searching the net, try to get access to a research database such as Jstor.