CREATE TABLE table_204_872 (id DECIMAL, "name" TEXT, "completed" TEXT, "architect" TEXT, "location" TEXT, "year of listing & ref ( s ) " DECIMAL)

which year has the most buildings listed ?
SELECT "year of listing & ref(s)" FROM table_204_872 GROUP BY "year of listing & ref(s)" ORDER BY COUNT("name") DESC LIMIT 1
SELECT "year of listing & ref(s)" FROM "table_204_872" GROUP BY "year of listing & ref(s)" ORDER BY COUNT("name") DESC NULLS LAST LIMIT 1