Every decade
No, a decade is every ten years, a century is every 100.
The word is... bicentennial.
Triennial
Every 100 years is called a century, made up of 10 decades.
The word century means 100 years FYI: decade means 10 years
each census is taken every 10 years
The word for every 75 years is "septuagesimal."
The word for every twenty years is "score."
I believe that the constitution states that one is to be done every 10 years.
The word Biennial means Every two years
7 of 10 leap years occur every years?
A synonym for every five years is quinquennial: as an adjective describes something that happens every five years or that lasts for five years; the noun means the fifth anniversary or a period of five years.
Every ten years=once a decade
"Decentennial" is not a recognized English word. It may be a misspelling or a made-up term. If you meant "decennial," it refers to something that occurs once every ten years.
every 10 years
Something that happens every three years is a triennialevent.
Sextennial means "Recurring every six years."