TheCodeBreakers
in a tactical sense, and the adjective "extraordinary" is probably justified
only under conditions of retreat and its accompanying confusion.
Army Group North, for example, read 5-digit code messages very
rarely. Of the intercepts in 2-, 3-, and 4-digit codes, it read 28.7 per
cent—13,312 messages out of 46,342 from the beginning of May, 1943,
to the end of May, 1944, a year in which the Russians pushed back the
northern sector of the front slightly, though not nearly as
ryccKUH, Jpuninujiu<:ufi 301
much as the southern. A month-by-month and system-by-system
breakdown of the cryptanalytic success of Army Group North (excluding
5-digit codes) shows a decline as the Russians improved their
cryptographic discipline.
As might be expected, the 2-digit systems, being the simplest,
succumbed the oftenest. However, fewer 3-digit than the presumably
more difficult 4-digit enciphered codes were solved, even though more 3-
digit messages were picked up
annaabi.ee 
