Merge pull request #46 from bodiyang/v4_development

V4 development
bodiyang · Jun 4, 2024 · 2794aa4 · 2794aa4
2 parents 802e20e + dcdf068
commit 2794aa4
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diff --git a/docs/guide/policy_params.md b/docs/guide/policy_params.md
diff --git a/taxcalc/calcfunctions.py b/taxcalc/calcfunctions.py
@@ -100,8 +100,9 @@ def BenefitPrograms(calc):
 
 @iterate_jit(nopython=True)
 def EI_PayrollTax(SS_Earnings_c, e00200p, e00200s, pencon_p, pencon_s,
-                  FICA_ss_trt, FICA_mc_trt, ALD_SelfEmploymentTax_hc,
-                  SS_Earnings_thd, SECA_Earnings_thd,
+                  FICA_ss_trt_employer, FICA_ss_trt_employee, 
+                  FICA_mc_trt_employer, FICA_mc_trt_employee, 
+                  ALD_SelfEmploymentTax_hc, SS_Earnings_thd, SECA_Earnings_thd,
                   e00900p, e00900s, e02100p, e02100s, k1bx14p,
                   k1bx14s, payrolltax, ptax_was, setax, c03260, ptax_oasdi,
                   sey, earned, earned_p, earned_s,
@@ -123,10 +124,14 @@ def EI_PayrollTax(SS_Earnings_c, e00200p, e00200s, pencon_p, pencon_s,
         Contributions to defined-contribution pension plans for taxpayer
     pencon_s: float
         Contributions to defined-contribution pension plans for spouse
-    FICA_ss_trt: float
-        Social security payroll tax rate, including both employer and employee
-    FICA_mc_trt: float
-        Medicare payroll tax rate, including both employer and employee
+    FICA_ss_trt_employer: float
+        Employer side social security payroll tax rate
+    FICA_ss_trt_employee: float
+        Employee side social security payroll tax rate    
+    FICA_mc_trt_employer: float
+        Employer side medicare payroll tax rate
+    FICA_mc_trt_employee: float
+        Employee side medicare payroll tax rate
     ALD_SelfEmploymentTax_hc: float
         Adjustment for self-employment tax haircut
         If greater than zero, reduces the employer equivalent portion of self-employment adjustment
@@ -218,22 +223,22 @@ def EI_PayrollTax(SS_Earnings_c, e00200p, e00200s, pencon_p, pencon_s,
     txearn_was_s = min(SS_Earnings_c, gross_was_s)
 
     # compute OASDI and HI payroll taxes on wage-and-salary income, FICA
-    ptax_ss_was_p = FICA_ss_trt * txearn_was_p
-    ptax_ss_was_s = FICA_ss_trt * txearn_was_s
-    ptax_mc_was_p = FICA_mc_trt * gross_was_p
-    ptax_mc_was_s = FICA_mc_trt * gross_was_s
+    ptax_ss_was_p = (FICA_ss_trt_employer + FICA_ss_trt_employee) * txearn_was_p
+    ptax_ss_was_s = (FICA_ss_trt_employer + FICA_ss_trt_employee) * txearn_was_s
+    ptax_mc_was_p = (FICA_mc_trt_employer + FICA_mc_trt_employee) * gross_was_p
+    ptax_mc_was_s = (FICA_mc_trt_employer + FICA_mc_trt_employee) * gross_was_s
     ptax_was = ptax_ss_was_p + ptax_ss_was_s + ptax_mc_was_p + ptax_mc_was_s
 
     # compute taxable self-employment income for OASDI SECA
-    sey_frac = 1.0 - 0.5 * (FICA_ss_trt + FICA_mc_trt)
+    sey_frac = 1.0 - 0.5 * (FICA_ss_trt_employer + FICA_ss_trt_employee + FICA_mc_trt_employer + FICA_mc_trt_employee)
     txearn_sey_p = min(max(0., sey_p * sey_frac), SS_Earnings_c - txearn_was_p)
     txearn_sey_s = min(max(0., sey_s * sey_frac), SS_Earnings_c - txearn_was_s)
 
     # compute self-employment tax on taxable self-employment income, SECA
-    setax_ss_p = FICA_ss_trt * txearn_sey_p
-    setax_ss_s = FICA_ss_trt * txearn_sey_s
-    setax_mc_p = FICA_mc_trt * max(0., sey_p * sey_frac)
-    setax_mc_s = FICA_mc_trt * max(0., sey_s * sey_frac)
+    setax_ss_p = (FICA_ss_trt_employer + FICA_ss_trt_employee) * txearn_sey_p
+    setax_ss_s = (FICA_ss_trt_employer + FICA_ss_trt_employee) * txearn_sey_s
+    setax_mc_p = (FICA_mc_trt_employer + FICA_mc_trt_employee) * max(0., sey_p * sey_frac)
+    setax_mc_s = (FICA_mc_trt_employer + FICA_mc_trt_employee) * max(0., sey_s * sey_frac)
     setax_p = setax_ss_p + setax_mc_p
     setax_s = setax_ss_s + setax_mc_s
     setax = setax_p + setax_s
@@ -246,13 +251,13 @@ def EI_PayrollTax(SS_Earnings_c, e00200p, e00200s, pencon_p, pencon_s,
     # compute extra OASDI payroll taxes on the portion of the sum
     # of wage-and-salary income and taxable self employment income
     # that exceeds SS_Earnings_thd
-    sey_frac = 1.0 - 0.5 * FICA_ss_trt
+    sey_frac = 1.0 - 0.5 * (FICA_ss_trt_employer + FICA_ss_trt_employee) 
     was_plus_sey_p = gross_was_p + max(0., sey_p * sey_frac)
     was_plus_sey_s = gross_was_s + max(0., sey_s * sey_frac)
     extra_ss_income_p = max(0., was_plus_sey_p - SS_Earnings_thd)
     extra_ss_income_s = max(0., was_plus_sey_s - SS_Earnings_thd)
-    extra_payrolltax = (extra_ss_income_p * FICA_ss_trt +
-                        extra_ss_income_s * FICA_ss_trt)
+    extra_payrolltax = (extra_ss_income_p * (FICA_ss_trt_employer + FICA_ss_trt_employee)  +
+                        extra_ss_income_s * (FICA_ss_trt_employer + FICA_ss_trt_employee))
 
     # compute part of total payroll taxes for filing unit
     # (the ptax_amc part of total payroll taxes for the filing unit is
@@ -1080,7 +1085,8 @@ def ItemDed(e17500_capped, e18400_capped, e18500_capped, e19200_capped,
 @iterate_jit(nopython=True)
 def AdditionalMedicareTax(e00200, MARS,
                           AMEDT_ec, sey, AMEDT_rt,
-                          FICA_mc_trt, FICA_ss_trt,
+                          FICA_mc_trt_employer, FICA_mc_trt_employee,
+                          FICA_ss_trt_employer, FICA_ss_trt_employee,
                           ptax_amc, payrolltax):
     """
     Computes Additional Medicare Tax (Form 8959) included in payroll taxes.
@@ -1093,10 +1099,14 @@ def AdditionalMedicareTax(e00200, MARS,
         Additional Medicare Tax earnings exclusion
     AMEDT_rt: float
         Additional Medicare Tax rate
-    FICA_ss_trt: float
-        FICA Social Security tax rate
-    FICA_mc_trt: float
-        FICA Medicare tax rate
+    FICA_ss_trt_employer: float
+        Employer side FICA Social Security tax rate
+    FICA_ss_trt_employee: float
+        Employee side FICA Social Security tax rate
+    FICA_mc_trt_employer: float
+        Employer side FICA Medicare tax rate
+    FICA_mc_trt_employee: float
+        Employee side FICA Medicare tax rate        
     e00200: float
         Wages and salaries
     sey: float
@@ -1113,7 +1123,7 @@ def AdditionalMedicareTax(e00200, MARS,
     payrolltax: float
         payroll tax augmented by Additional Medicare Tax
     """
-    line8 = max(0., sey) * (1. - 0.5 * (FICA_mc_trt + FICA_ss_trt))
+    line8 = max(0., sey) * (1. - 0.5 * (FICA_mc_trt_employer + FICA_mc_trt_employee + FICA_ss_trt_employer + FICA_ss_trt_employee))
     line11 = max(0., AMEDT_ec[MARS - 1] - e00200)
     ptax_amc = AMEDT_rt * (max(0., e00200 - AMEDT_ec[MARS - 1]) +
                            max(0., line8 - line11))
@@ -2149,15 +2159,23 @@ def F2441(MARS, earned_p, earned_s, f2441, CDCC_c, e32800,
     c00100: float
         Adjusted Gross Income (AGI)
     CDCC_ps: float
-        Child/dependent care credit phaseout start
+        Child/dependent care credit first phaseout start
+    CDCC_ps2: float
+        Child/dependent care credit second phaseout start
     CDCC_crt: float
-        Child/dependent care credit phaseout percentage rate ceiling
+        Child/dependent care credit phaseout rate ceiling
+    CDCC_frt: float
+        Child/dependent care credit phaseout rate floor
+    CDCC_prt: float
+        Child/dependent care credit phaseout rate
     c05800: float
         Total (regular + AMT) income tax liability before credits
     e07300: float
         Foreign tax credit from Form 1116
     c07180: float
         Credit for child and dependent care expenses from Form 2441
+    CDCC_refund: bool
+        Indicator for whether CDCC is refundable
 
     Returns
     -------
@@ -2189,7 +2207,8 @@ def F2441(MARS, earned_p, earned_s, f2441, CDCC_c, e32800,
         if c00100 > CDCC_ps2:
             crate = max(0., CDCC_frt -
                         max(((c00100 - CDCC_ps2) * CDCC_prt), 0.))
-    c33200 = c33000 * 0.01 * crate
+
+    c33200 = c33000 * crate
     # credit is limited by tax liability if not refundable
     if CDCC_refundable:
         c07180 = 0.

diff --git a/taxcalc/calculator.py b/taxcalc/calculator.py
@@ -694,9 +694,11 @@ def mtr(self, variable_str='e00200p',
                 variable >= self.policy_param('SS_Earnings_thd')
             )
             adj = np.where(oasdi_taxed,
-                           0.5 * (self.policy_param('FICA_ss_trt') +
-                                  self.policy_param('FICA_mc_trt')),
-                           0.5 * self.policy_param('FICA_mc_trt'))
+                           0.5 * (self.policy_param('FICA_ss_trt_employer') +
+                                  self.policy_param('FICA_ss_trt_employee') +
+                                  self.policy_param('FICA_mc_trt_employer') +
+                                  self.policy_param('FICA_mc_trt_employee')),
+                           0.5 * (self.policy_param('FICA_mc_trt_employer') + self.policy_param('FICA_mc_trt_employee')))
         else:
             adj = 0.0
         # compute marginal tax rates

diff --git a/taxcalc/parameters.py b/taxcalc/parameters.py
@@ -61,7 +61,7 @@ class Parameters(pt.Parameters):
                 print(name, value)
 
             # parameter_indexing_CPI_offset [0.]
-            # FICA_ss_trt [0.124]
+            # FICA_ss_trt_employer [0.062]
             # SS_Earnings_c [113700.]
 
     Check out the ParamTools

diff --git a/taxcalc/policy_current_law.json b/taxcalc/policy_current_law.json
@@ -117,9 +117,9 @@
             "cps": true
         }
     },
-    "FICA_ss_trt": {
-        "title": "Social Security payroll tax rate",
-        "description": "Social Security FICA rate, including both employer and employee.",
+    "FICA_ss_trt_employer": {
+        "title": "Employer side Social Security payroll tax rate",
+        "description": "Employer side Social Security FICA rate, including both employer and employee.",
         "notes": "",
         "section_1": "Payroll Taxes",
         "section_2": "Social Security FICA",
@@ -129,13 +129,39 @@
         "value": [
             {
                 "year": 2013,
-                "value": 0.124
+                "value": 0.062
             }
         ],
         "validators": {
             "range": {
                 "min": 0,
-                "max": 1
+                "max": 0.5
+            }
+        },
+        "compatible_data": {
+            "puf": true,
+            "cps": true
+        }
+    },
+    "FICA_ss_trt_employee": {
+        "title": "Employee side Social Security payroll tax rate",
+        "description": "Employee side Social Security FICA rate, including both employer and employee.",
+        "notes": "",
+        "section_1": "Payroll Taxes",
+        "section_2": "Social Security FICA",
+        "indexable": false,
+        "indexed": false,
+        "type": "float",
+        "value": [
+            {
+                "year": 2013,
+                "value": 0.062
+            }
+        ],
+        "validators": {
+            "range": {
+                "min": 0,
+                "max": 0.5
             }
         },
         "compatible_data": {
@@ -257,9 +283,9 @@
             "cps": true
         }
     },
-    "FICA_mc_trt": {
-        "title": "Medicare payroll tax rate",
-        "description": "Medicare FICA rate, including both employer and employee.",
+    "FICA_mc_trt_employer": {
+        "title": "Employer side Medicare payroll tax rate",
+        "description": "Employer side Medicare FICA rate, including both employer and employee.",
         "notes": "",
         "section_1": "Payroll Taxes",
         "section_2": "Medicare FICA",
@@ -269,13 +295,39 @@
         "value": [
             {
                 "year": 2013,
-                "value": 0.029
+                "value": 0.0145
             }
         ],
         "validators": {
             "range": {
                 "min": 0,
-                "max": 1
+                "max": 0.5
+            }
+        },
+        "compatible_data": {
+            "puf": true,
+            "cps": true
+        }
+    },
+    "FICA_mc_trt_employee": {
+        "title": "Employee side Medicare payroll tax rate",
+        "description": "Employee side Medicare FICA rate, including both employer and employee.",
+        "notes": "",
+        "section_1": "Payroll Taxes",
+        "section_2": "Medicare FICA",
+        "indexable": false,
+        "indexed": false,
+        "type": "float",
+        "value": [
+            {
+                "year": 2013,
+                "value": 0.0145
+            }
+        ],
+        "validators": {
+            "range": {
+                "min": 0,
+                "max": 0.5
             }
         },
         "compatible_data": {
@@ -16350,8 +16402,8 @@
         }
     },
     "CDCC_crt": {
-        "title": "Child & dependent care credit phaseout percentage rate ceiling",
-        "description": "The maximum percentage rate for the CDCC; this percentage rate decreases as AGI rises above the CDCC_ps level.",
+        "title": "Child & dependent care credit phaseout rate ceiling",
+        "description": "The maximum rate for the CDCC; this rate decreases as AGI rises above the CDCC_ps level.",
         "notes": "",
         "section_1": "Nonrefundable Credits",
         "section_2": "Child And Dependent Care",
@@ -16361,21 +16413,21 @@
         "value": [
             {
                 "year": 2013,
-                "value": 35.0
+                "value": 0.350
             },
             {
                 "year": 2021,
-                "value": 50.0
+                "value": 0.500
             },
             {
                 "year": 2022,
-                "value": 35.0
+                "value": 0.350
             }
         ],
         "validators": {
             "range": {
                 "min": 0,
-                "max": 100
+                "max": 1
             }
         },
         "compatible_data": {
@@ -16384,8 +16436,8 @@
         }
     },
     "CDCC_frt": {
-        "title": "Child & dependent care credit phaseout percentage rate floor",
-        "description": "The minimum percentage rate for the first AGI phaseout of the CDCC.",
+        "title": "Child & dependent care credit phaseout rate floor",
+        "description": "The minimum rate for the first AGI phaseout of the CDCC.",
         "notes": "",
         "section_1": "Nonrefundable Credits",
         "section_2": "Child And Dependent Care",
@@ -16395,13 +16447,13 @@
         "value": [
             {
                 "year": 2013,
-                "value": 20.0
+                "value": 0.200
             }
         ],
         "validators": {
             "range": {
                 "min": 0,
-                "max": 100
+                "max": 1
             }
         },
         "compatible_data": {
@@ -16410,9 +16462,9 @@
         }
     },
     "CDCC_prt": {
-        "title": "Child & dependent care credit phaseout percentage rate",
-        "description": "The CDCC credit rate is reduced by this many percentage points for each dollary of AGI over the phase-out thresholds.",
-        "notes": "In the law, the credit rate is reduced by 1 percentage point for every $2,000 of AGI over the limit.",
+        "title": "Child & dependent care credit phaseout rate",
+        "description": "The CDCC credit rate is reduced by this many percentage points for each dollar of AGI over the phase-out thresholds.",
+        "notes": "In the law, the credit rate is reduced by 1 percentage point for every $2,000 of AGI over the limit. 0.01 / 2000 = 0.000005",
         "section_1": "Nonrefundable Credits",
         "section_2": "Child And Dependent Care",
         "indexable": false,
@@ -16421,7 +16473,7 @@
         "value": [
             {
                 "year": 2013,
-                "value": 0.0005
+                "value": 5e-06
             }
         ],
         "validators": {

diff --git a/taxcalc/reforms/ARPA.json b/taxcalc/reforms/ARPA.json
@@ -61,8 +61,8 @@
                 "2022": 15000},
     "CDCC_ps2": {"2021": 400000,
                  "2022": 9e+99},
-    "CDCC_crt": {"2021": 50.0,
-                 "2022": 35.0},
+    "CDCC_crt": {"2021": 0.5,
+                 "2022": 0.35},
     "CDCC_refundable": {"2021": true,
                         "2022": false},
     "ALD_BusinessLosses_c": {"2026": [283535.22, 567070.42, 283535.22, 283535.22, 567070.42],