CREATE TABLE table_23455 ("Number" FLOAT, "Registration" CLOB, "First flew" CLOB, "Last flew" CLOB, "Flying hours" FLOAT, "Location" CLOB)

on 19 april 1985 how many of number last flew
SELECT COUNT("Number") FROM table_23455 WHERE "Last flew" = '19 April 1985'
SELECT COUNT("Number") FROM "table_23455" WHERE "Last flew" = '19 April 1985'