Fix Arkansas 2014-2020 income tax rate schedules

changelog.d/fix-ar-pre-2021-rate-schedules.fixed.md

@@ -0,0 +1 @@
+Arkansas 2014-2020 income tax schedules now follow DFA's Indexed Tax Brackets, which reproduce every row of DFA's Regular Tax Tables: the 2014-2020 subtraction amounts are added, and the 2016-2018 rates, thresholds and high-income bracket adjustments are corrected.

policyengine_us/parameters/gov/states/ar/tax/income/rates/main/rate.yaml

@@ -8,12 +8,28 @@ metadata:
   reference:
   - title: Tax Legislation for 2022 Ark. Code § 26-51-201 (a)(1)(A) # (d)(1) for uprating.
     href: https://casetext.com/statute/arkansas-code-of-1987/title-26-taxation/subtitle-5-state-taxes/chapter-51-income-taxes/subchapter-2-imposition-of-tax/section-26-51-201-effective-90-days-after-sine-die-adjournment-individuals-trusts-and-estates
+  - title: Arkansas Act 1459 of 2013, § 1 (0.9% first bracket from tax year 2014)
+    href: https://www.arkleg.state.ar.us/Acts/FTPDocument?path=%2FACTS%2F2013R%2FPublic%2F&file=1459.pdf&ddBienniumSession=2013%2F2013R#page=1
+  - title: Arkansas Act 22 of 2015, § 2, amending Ark. Code § 26-51-201(a) (tax year 2014-2018 tables and the bracket adjustment above $75,000)
+    href: https://www.arkleg.state.ar.us/Acts/FTPDocument?path=%2FACTS%2F2015R%2FPublic%2F&file=22.pdf&ddBienniumSession=2015%2F2015R#page=1
+  - title: Arkansas Act 78 of 2017, § 2, amending Ark. Code § 26-51-201(a)(7)-(8) (tax year 2019)
+    href: https://www.arkleg.state.ar.us/Acts/FTPDocument?path=%2FACTS%2F2017R%2FPublic%2F&file=78.pdf&ddBienniumSession=2017%2F2017R#page=1
+  - title: Arkansas Act 182 of 2019, § 3, amending Ark. Code § 26-51-201(a)(7)-(10) (tax year 2020)
+    href: https://www.arkleg.state.ar.us/Acts/FTPDocument?path=%2FACTS%2F2019R%2FPublic%2F&file=182.pdf&ddBienniumSession=2019%2F2019R#page=2
+  - title: 2014 Indexed Tax Brackets (DFA sheet, archived copy)
+    href: https://web.archive.org/web/20150105194030/http://www.dfa.arkansas.gov/offices/incomeTax/individual/Documents/TaxBrackets_2014.pdf
   - title: 2014 AR1000F and AR1000NR Instructions (tax bracket reduced to 0.9% for 2014)
     href: https://www.dfa.arkansas.gov/wp-content/uploads/LongBookwTaxTables_2014.pdf#page=6
   - title: 2014 AR1000F and AR1000NR Instructions (2014 Regular Tax Table)
     href: https://www.dfa.arkansas.gov/wp-content/uploads/LongBookwTaxTables_2014.pdf#page=28
   - title: 2015 Indexed Tax Brackets
     href: https://www.dfa.arkansas.gov/wp-content/uploads/TaxBrackets_2015.pdf#page=1
+  - title: 2016 Indexed Tax Brackets
+    href: https://www.dfa.arkansas.gov/wp-content/uploads/Tax%20Brackets_2016.pdf#page=1
+  - title: 2017 Indexed Tax Brackets
+    href: https://www.dfa.arkansas.gov/wp-content/uploads/TaxBrackets2017.pdf#page=1
+  - title: 2018 Indexed Tax Brackets
+    href: https://www.dfa.arkansas.gov/wp-content/uploads/2018_Tax_Brackets.pdf#page=1
   - title: 2019 Indexed Tax Brackets
     href: https://www.dfa.arkansas.gov/wp-content/uploads/TaxBrackets_2019.pdf#page=1
   - title: 2020 Indexed Tax Brackets
@@ -49,6 +65,8 @@ brackets:
   - threshold:
       values:
         2014-01-01: 4_300
+        2017-01-01: 4_400
+        2018-01-01: 4_500
         2019-01-01: 4_600
         2020-01-01: 4_700
         2021-01-01: 4_800
@@ -70,6 +88,9 @@ brackets:
   - threshold:
       values:
         2014-01-01: 8_400
+        2016-01-01: 8_500
+        2017-01-01: 8_700
+        2018-01-01: 8_900
         2019-01-01: 9_100
         2020-01-01: 9_200
         2021-01-01: 9_500
@@ -92,6 +113,8 @@ brackets:
       values:
         2014-01-01: 12_600
         2015-01-01: 12_700
+        2017-01-01: 13_100
+        2018-01-01: 13_400
         2019-01-01: 13_700
         2020-01-01: 13_900
         2021-01-01: 14_300
@@ -114,6 +137,9 @@ brackets:
       values:
         2014-01-01: 21_000
         2015-01-01: 21_100
+        2016-01-01: 21_200
+        2017-01-01: 21_700
+        2018-01-01: 22_200
         2019-01-01: 22_600
         2020-01-01: 22_900
         2021-01-01: 23_600
@@ -130,7 +156,7 @@ brackets:
             interval: 100
     amount:
       2014-01-01: 0.06
-      2019-01-01: 0.05
+      2016-01-01: 0.05
       2022-01-01: 0.049
       2023-01-01: 0.047
       2024-01-01: 0.039
@@ -139,6 +165,9 @@ brackets:
       values:
         2014-01-01: 35_100
         2015-01-01: 35_300
+        2016-01-01: 35_100
+        2017-01-01: 36_300
+        2018-01-01: 37_200
         2019-01-01: 37_900
         2020-01-01: 38_500
         2021-01-01: 39_700
@@ -151,13 +180,16 @@ brackets:
             interval: 100
     amount:
       2014-01-01: 0.07
-      2019-01-01: 0.06
+      2016-01-01: 0.06
       2020-01-01: 0.059
       2022-01-01: .inf
   - threshold:
       values:
         2014-01-01: .inf
-        2019-01-01: 80_801 
+        2016-01-01: 75_001
+        2017-01-01: 77_401
+        2018-01-01: 79_301
+        2019-01-01: 80_801
         2020-01-01: 82_001
         2021-01-01: .inf
       metadata:
@@ -168,6 +200,6 @@ brackets:
             interval: 100
     amount:
       2014-01-01: .inf
-      2019-01-01: 0.069
+      2016-01-01: 0.069
       2020-01-01: 0.066
       2021-01-01: .inf