CREATE TABLE table_76815 ("1976" TEXT, "1977" TEXT, "1978" TEXT, "1979" TEXT, "1980" TEXT)

what is 1977 when 1978 is 4.1?
SELECT "1977" FROM table_76815 WHERE "1978" = '4.1'
SELECT "1977" FROM "table_76815" WHERE "1978" = '4.1'