One quick and dirty way to break out the numbers would be to create a danger number which would be 100 minus the 1 to 100 integrity scale This could be the formula danger factor daily volume 100 bridge integrity rating So a perfect bridge with 300 000 cars a day would rate a 0 A bridge with a 75 integrity rating and 10 000 cars would get a 2 500 score and the I 35W bridge with 141 000 vehicles per day and a 50 integrityh rating would get a danger score of 70 500 I m sure the I 35W bridge would nearly top this list that accounts for vehicle volume and structural integrity