It is impossible to say how many people have a certain name. Not all countries register all births and record such things. Nor is there any centralised register.
In addition similar names can be totally different in different languages and contractions of names differ from place to place.
Spencer Redford's birth name is Jessica Spencer.
Spencer Haywood's birth name is Spencer Haywood.
Christopher Spencer's full name is Christopher Miner Spencer.
Spencer Showalter's birth name is Spencer Barrett Showalter.
Spencer Rochfort's birth name is Spencer D'Oyly Rochfort.
Spencer Roy's birth name is Samit Spencer Roy.
Spencer Sutton's birth name is Sutton, Spencer Cory.
Abigail Spencer's birth name is Abigail Leigh Spencer.
Brenda Spencer's birth name is Brenda Ann Spencer.
Charity Spencer's birth name is Charity Jean Spencer.
Dominique Spencer's birth name is Dominique Antonio Spencer.
Felton Spencer's birth name is Felton LaFrance Spencer.