CREATE TABLE table_72202 ("Acquisition" TEXT, "knowledge" TEXT, "penance" TEXT, "permanence of the body" TEXT, "constancy" TEXT, "purity" TEXT)

what is the total number of constancy where purity is falling
SELECT COUNT("constancy") FROM table_72202 WHERE "purity" = 'falling'
SELECT COUNT("constancy") FROM "table_72202" WHERE "purity" = 'falling'