CREATE TABLE table_22491 ("Township" TEXT, "County" TEXT, "Pop.  ( 2010 ) " FLOAT, "Land  (  sqmi  ) " TEXT, "Water  ( sqmi ) " TEXT, "Latitude" TEXT, "Longitude" TEXT, "GEO ID" FLOAT, "ANSI code" FLOAT)

Name the number of county for 90 population
SELECT COUNT("County") FROM table_22491 WHERE "Pop. (2010)" = '90'
SELECT COUNT("County") FROM "table_22491" WHERE "Pop. (2010)" = '90'