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Table 4.
Calculation of the Weighted Conversion Factors Used to Change the Volume of Large Pine Sawtimber and Hardwood Sawtimber Measured in International 1/4 inch Log Rule to Doyle Log Rule

Diameter Class Volume in Million bd. ft. International 1/4" Log Rule   Total Volume   Percent of Total Volume   Conversion Factor   Weighted Contribution
PINE
11 - 12.9 5,195.1 ÷ 24,003.10 = 21.64% x 0.4904 x 0.10612
13 - 14.9 5,365.1 ÷ 24,003.10 = 22.35% x 0.5246 x 0.11725
15 - 16.9 4,855.0 ÷ 24,003.10 = 20.23% x 0.5912 x 0.11960
17 - 18.9 3,468.3 ÷ 24,003.10 = 14.45% x 0.6527 x 0.09432
19 - 20.9 2,136.7 ÷ 24,003.10 = 8.90% x 0.7065 x 0.06288
21 - 28.9 2,629.3 ÷ 24,003.10 = 10.95% x 0.8115 x 0.08886
29+ 353.6 ÷ 24,003.10 = 1.47% x 0.9218 x 0.01355
  24,003.10       99.99%       0.60258
Weighted Conversion Factor for Large Pine Sawtimber = 0.60258
HARDWOOD
11 - 12.9 2,428.4 ÷ 14,434.50 = 16.82% x 0.4638 x 0.07801
13 - 14.9 2,868.1 ÷ 14,434.50 = 19.87% x 0.5292 x 0.10516
15 - 16.9 2,454.5 ÷ 14,434.50 = 17.00% x 0.5913 x 0.10052
17 - 18.9 2,080.3 ÷ 14,434.50 = 14.41% x 0.6460 x 0.09309
19 - 20.9 1,525.6 ÷ 14,434.50 = 10.57% x 0.6933 x 0.07328
21 - 28.9 2,571.3 ÷ 14,434.50 = 17.81% x 0.7841 x 0.13965
29+ 506.3 ÷ 14,434.50 = 3.51% x 0.8732 x 0.03065
  14,434.5       99.99%       0.62036
Weighted Conversion Factor for Hardwood Sawtimber = 0.62036
Volume Data from United States Forest Service, Forest Inventory and Analysis
Conversion Factors for International 1/4 Inch Log Rule to Doyle Log Rule from Mississippi State Study conducted by Thomas Matney
Conversion Factors for Doyle Log Rule to Tons from Texas Forest Service