This study provides acoustic evidence that in the
last 50 years New Zealand English (NZE) has undergone a
substantial vowel shift. Two sets of data are studied:
the Otago corpus, recorded in 1995, and the Mobile Unit
corpus, recorded in 1948. Both corpora have male and female
speakers. The corpora were labeled, accented vowels were
extracted, and formant values were calculated. The results
of the formant analysis from the two corpora are contrasted.
We provide evidence that in NZE /i/ has centralized, /e/
and /æ/ have raised, and the diphthongs /i[inverted e]/
and /e[inverted e]/ have merged. We argue that /i/ changed in
quality not only because of crowding in the front vowel space,
but also because it would be less likely misperceived as
an unaccented vowel (i.e., as [inverted e]).