CREATE TABLE table_73268 ("Gas name" CLOB, "Chemical formula" CLOB, "Lifetime  ( years ) " CLOB, "20-yr" CLOB, "100-yr" CLOB, "500-yr" CLOB)

What is the 100 year when 500 year is 153?
SELECT "100-yr" FROM table_73268 WHERE "500-yr" = '153'
SELECT "100-yr" FROM "table_73268" WHERE "500-yr" = '153'