1920 1929 1950
Electrical manufactures 26,1% 22,5% 20,0%
Telephones and telegraphs 7,7 14,4 6,0
Light and power lines 14,6 11,0 7,0
Railways and ships 9,8 1,4 4,0
Automobiles 7,6 11,9 10,0
Buildings 4,1 5,1 10,0
Radio and television 0,0 1,3 4,0