Penned record covering a number of years (5)
I believe the answer is:
caged
'penned' is the definition.
(thesaurus)
'record covering a number of years' is the wordplay.
'record' becomes 'cd' (I've seen this in other clues).
'covering' is an insertion indicator.
'a number of years' becomes 'age' (I've seen this in other clues).
'cd' going around 'age' is 'CAGED'.
(Other definitions for caged that I've seen before include "In a zoo?" , "Confined behind bars" , "Shut up" , "Cooped up" , "in prison" .)