CREATE TABLE table_54676 ("Date" TEXT, "Visitor" TEXT, "Score" TEXT, "Home" TEXT, "Decision" TEXT, "Attendance" FLOAT, "Series" TEXT)

On April 28, what was the average number of people attending?
SELECT AVG("Attendance") FROM table_54676 WHERE "Date" = 'april 28'
SELECT AVG("Attendance") FROM "table_54676" WHERE "Date" = 'april 28'