It is hoped that, unlike the earlier edition, it will be subjected to continual updating, if not annually then at least quinquennially.    From Wordnik.com.  [VERBATIM: The Language Quarterly Vol XIV No 3] Reference

How rapidly the traffic attracted by the economy in distance thus effected has developed, is best illustrated by the following statement, taken quinquennially from the company's returns.    From Wordnik.com.  [East of Suez Ceylon, India, China and Japan] Reference

Each of the new Provinces of Alberta and Saskatchewan are to be paid a per capita allowance on a minimum population of 250,000, increasing quinquennially from 1901 until a maximum population of 800,000 souls is attained-twice that in the Maritime Provinces, and but little over one-half of that in Ontario.    From Wordnik.com.  [North-West Autonomy] Reference

(This increases quinquennially till it becomes.    From Wordnik.com.  [North-West Autonomy] Reference