The letter B occurs, on average, once in every hundred letters of standard English prose. So, too, do the letters G and V. By contrast, those same hundred letters will include 13 E's, 9 T's, and 4 D's, but J, K, Q, X, and Z will, in all probability, be completely absent. Assigning individual letter values which reflect a realistic view of their frequency of use int he language and including decimal points up to 0.5, we have the following tables:
"Sumwords: A New Crossword Game,"
Word Ways: Vol. 23
, Article 13.
Available at: http://digitalcommons.butler.edu/wordways/vol23/iss1/13