Who ghost-wrote for the Bard?

The real author behind Shakespeare's plays and poems has been subject to a controversy dating back about 150 years. The so-called "Anti-Stratfordians" maintain that Shakespeare, with his provincial background (from Stratford-upon-Avon) could not possibly have collected sufficient knowledge and education to be accountable for his body of work. The most popular candidates as the Bard's ghostwriters are Francis Bacon (1561-1626) and Edward de Vere, the 17th Earl of Oxford (1550-1604); the latter being favored by some on the grounds of Shakespeare's complete lack of productivity during the last decade of his life until 1616.