user: Question: Which Diameter has a Year of Issue of 1977?
Columns: ['Year of Issue', 'Weight', 'Diameter', 'Thickness', 'Edge']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [1976.0, '3.24grams', '19.05mm', '1.42mm', 'Plain']
SQL:

assistant: SELECT "Diameter" FROM "Table" WHERE "Year of Issue" = 1977.0;