CREATE TABLE table_5228 ("Season" TEXT, "Tier" FLOAT, "League" TEXT, "Pos." FLOAT, "Postseason" TEXT, "European competitions" TEXT)

What is the total number of tiers for the postseason of semifinalist?
SELECT SUM("Tier") FROM table_5228 WHERE "Postseason" = 'semifinalist'
SELECT SUM("Tier") FROM "table_5228" WHERE "Postseason" = 'semifinalist'