CREATE TABLE table_46429 ("Finished" FLOAT, "Time/ Behind" TEXT, "Post" FLOAT, "Horse" TEXT, "Jockey" TEXT, "Trainer" TEXT, "Owner" TEXT)

What is the total number of Post, when Trainer is 'Steve Asmussen', and when Time/ Behind is 19 ?
SELECT COUNT("Post") FROM table_46429 WHERE "Trainer" = 'steve asmussen' AND "Time/ Behind" = '19 ½'
SELECT COUNT("Post") FROM "table_46429" WHERE "Time/ Behind" = '19 ½' AND "Trainer" = 'steve asmussen'