CREATE TABLE table_30800 ("Player" TEXT, "Matches" FLOAT, "Overs" TEXT, "Wickets" FLOAT, "Average" TEXT, "Economy" TEXT, "BBI" TEXT, "4wi" FLOAT)

What is the BBI whent the economy is 5.68?
SELECT "BBI" FROM table_30800 WHERE "Economy" = '5.68'
SELECT "BBI" FROM "table_30800" WHERE "Economy" = '5.68'