[Internet Archive June 23, 2012] Any set of statistics about word frequencies in Latin will inevitably be, in the absence of a survey covering all classical texts (however one might define "classical" or "text"), a function of the specific works and passages chosen for the database. This collection is drawn from two word counts made much earlier in this century...
These lists were compiled from a largely prose corpus of about 5.3 million Latin words, including many post-classical sources. In this second edition, the many repetitions of the first edition have largely been eliminated, along with numerals and contractions, but the proper names have been retained. Also, the letters v and j have all been converted into the letters u and i. Thus the numeral VI was necessarily concordanced with the ablative of vis and appears as ui. For this and other reasons, these lists are only a rough approximation to the order of frequency. Note that each word's inflected forms are concordanced separately.
J. Untermann, and P. von Martitz. Der altsprachliche Unterricht. Arbeitshefte zu seiner wissenschaftlichen Begründung und praktischen Gestalt, 24 (4):
24-54(1981)
B. McGillivray. Proceedings of the ACL 2010 Student Research Workshop, page 73--78. Stroudsburg, PA, USA, Association for Computational Linguistics, (2010)