CREATE TABLE table_68862 ("Episode No." FLOAT, "Airdate" CLOB, "Total Viewers" FLOAT, "Share" CLOB, "BBC One Weekly Ranking" CLOB)

What's the average total viewers that has 17.6% Share?
SELECT AVG("Total Viewers") FROM table_68862 WHERE "Share" = '17.6%'
SELECT AVG("Total Viewers") FROM "table_68862" WHERE "Share" = '17.6%'