CREATE TABLE table_69987 ("Lot No." FLOAT, "Diagram" FLOAT, "Built" CLOB, "Builder" CLOB, "Fleet numbers" CLOB)

What is the total diagram for builder york?
SELECT SUM("Diagram") FROM table_69987 WHERE "Builder" = 'york'
SELECT SUM("Diagram") FROM "table_69987" WHERE "Builder" = 'york'