The Multnomah county (Oregon) form SP-2021 county tax calculation has a bug that causes it to under calculate the amount of tax owed. If you have some amount on line 18, and "0" on line 19, line 20 is supposed to be the sum of lines 18 and 19. Instead it incorrectly calculated "0" for line 20. This causes it to calculate "0" as your tax owed, when it should be at least $100 minimum.
