Year	Billion Current Dollars
1921	3.98700
1922	5.54000
1923	6.75800
1924	7.59700
1925	8.39900
1926	9.01000
1927	8.66500
1928	8.45400
1929	7.78100
1930	5.60400
1931	3.55700
1932	1.67100
1933	1.15200
1934	1.41100
1935	1.87400
1936	2.78900
1937	3.71200
1938	3.29300
1939	4.00000