Don't forget NC has been written by the enumerator - plus Norfolk County - Northumberland would not make sense in any case
No - NC has been written by the householder , (text deleted.) It doesn't say NC Northumberland , just NC ,and could just as easily stand for Norfolk , Corpusty - perhaps Mr ? was just uncertain .( The 1911 census was filled in and signed by the householder or someone else in the house if he was unable to write )
( Edited by me for copyright reasons )