171 



Note 10. — Consumption of shingles on farms. 

 It is assumed that the same proportion of shingles is consumed on 

 farms as of lumber. This is 31.523 per cent of the total for the state. 

 This proportion of 5,516,110 cubic feet of shingles gives 1,738,788 cubic 

 feet consumed on farms, or 7.331 cubic feet per year. This is a total 

 of 193,11)8 M shingles, or Sl-t shingles per year on each farm, taking 

 no account of the substitutes for shingles, which considerably increase 

 the total of roofing used. 



Note 11. — Total coal and wood, 2,769,680 tons, converted to cords 

 by .8 equivalent and divided by 237,181 farms. 



Note 12. — Origin of data concerning consumption of lumber. 



In distributing the total quantity of lumber, 2,353,662,000 board feet, 

 consumed in the state in 1920, accurate statistical data are not available. 

 The results are approximate only, and are based on percentages derived 

 from previous studies and partial data. The total consumption of lum- 

 ber in the Chicago district in 1920 was 1,454,712,000 board feet*. This 

 agrees closely with the average for the decade 1911-21 of 1,466,820,300 

 board feet. In 1909 the total consumption of lumber in the Chicago 

 district was 1,622,690,000 board feet of which the building trades used 

 31.172 per cent, or 505,835,000 board feet, and the wood-using indus- 

 tries, 1,116,855,120 board feet or 68.83 per cent. 



Assuming that the same ratio of consumption applies between the 

 building trades and the total consumption in Chicago for 1920 as for 

 1909 and applying this 32 per cent to the total consumption in the Chi- 

 cago district for 1920 the building trades would have consumed in that 

 year 465,507,000 board feet, which would leave 989,205,000 board feet 

 for the wood-using industries of Chicago alone. The best information 

 available in Chicago for 1923 places the consumption by the building 

 trades at 600,000,000 feet, so that it seems safe to place the annual con- 

 sumption for that purpose at between 500 and 600 million feet, exclu- 

 sive of planing-mill products. 



That there has been a decrease in the total consumption of wood in 

 these wood-using industries in the last decade is indicated by the ap- 

 parently large decrease in the amount of hardwood timber shipped into 

 the state (page 98). The decrease in Chicago alone, on this basis, is 

 indicated as approximately 11.5 per cent since 1,116,855,120 board feet 

 was used in 1900 in these Chicago industries. Outside of Chicago the 



• Chicago Board of Trade. 



