 Ryman held off a strong challenge from Milne in the 1979 general election, holding his seat with a majority of over 7,000.The constituency was renamed Blyth Valley for the 1983 general election, when the newly formed Social Democratic Party (SDP) cut his majority to 3,243.In 1986, he announced that he was leaving the Labour Party and sat as an independent until he retired at the 1987 general election.