mˈoʊst ɹˈɛfɹənsᵻz sˈaɪt ɐbˌaʊt tˈɛn pɚsˈɛnt ʌv mˈɛsɪdʒᵻz pˈɑːɹʃəli ɔːɹ sˈʌmtaɪmz kəmplˈiːtli dᵻkɹˈɪptᵻd pɹˈaɪɚ tə dᵻsˈɛmbɚ wˈʌn, nˈaɪntiːnhˈʌndɹɪd fˈoːɹɾi wˈʌn, æt wˌɪtʃ tˈaɪm ɐ nˈuː vˈɜːʒən ʌvðə sˈɪstəm wɛnt ˌɪntʊ ɪfˈɛkt, ɹᵻkwˈaɪɚɹɪŋ ðə kɹɪptˈænɐlˌɪsts tə stˈɑːɹt ɐɡˈɛn.
Most references cite about 10% of messages partially (or sometimes completely) decrypted prior to December 1, 1941, at which time a new version of the system went into effect, requiring the cryptanalysts to start again.