how many times is the date (to) 1919?
CREATE TABLE "list_of_town_tramway_systems_in_the_neth" (
  "name_of_system" text,
  "location" text,
  "traction_type" text,
  "date_from" text,
  "date_to" text,
  "notes" text
);
SELECT COUNT("notes") FROM "list_of_town_tramway_systems_in_the_neth" WHERE "date_to"='1919';