Source code for taxcalc.policy

Tax-Calculator federal tax policy Policy class.
# pycodestyle
# pylint --disable=locally-disabled

import os
import json
import numpy as np
from taxcalc.parameters import Parameters
from taxcalc.growfactors import GrowFactors

[docs]class Policy(Parameters): """ Policy is a subclass of the abstract Parameters class, and therefore, inherits its methods (none of which are shown here). Constructor for the federal tax policy class. Parameters ---------- gfactors: GrowFactors class instance containing price inflation rates and wage growth rates Raises ------ ValueError: if gfactors is not a GrowFactors class instance or None. Returns ------- class instance: Policy """ DEFAULTS_FILE_NAME = 'policy_current_law.json' DEFAULTS_FILE_PATH = os.path.abspath(os.path.dirname(__file__)) JSON_START_YEAR = 2013 # remains the same unless earlier data added LAST_KNOWN_YEAR = 2022 # last year for which indexed param vals are known # should increase LAST_KNOWN_YEAR by one every calendar year LAST_BUDGET_YEAR = 2031 # last extrapolation year # should increase LAST_BUDGET_YEAR by one every calendar year DEFAULT_NUM_YEARS = LAST_BUDGET_YEAR - JSON_START_YEAR + 1 # NOTE: the following three data structures use internal parameter names: # (1) specify which Policy parameters have been removed or renamed REMOVED_PARAMS = { # following five parameters removed in PR 2223 merged on 2019-02-06 'DependentCredit_Child_c': 'is a removed parameter name', 'DependentCredit_Nonchild_c': 'is a removed parameter name', 'DependentCredit_before_CTC': 'is a removed parameter name', 'FilerCredit_c': 'is a removed parameter name', 'ALD_InvInc_ec_base_RyanBrady': 'is a removed parameter name', # TODO: following parameter renamed in PR 2292 merged on 2019-04-15 "cpi_offset": ( "was renamed parameter_indexing_CPI_offset. " "See documentation for change in usage." ), "CPI_offset": ( "was renamed parameter_indexing_CPI_offset. " "See documentation for change in usage." ), # TODO: following parameters renamed in PR 2345 merged on 2019-06-24 'PT_excl_rt': 'was renamed PT_qbid_rt in release 2.4.0', 'PT_excl_wagelim_thd': 'was renamed PT_qbid_taxinc_thd in release 2.4.0', 'PT_excl_wagelim_prt': 'was renamed PT_qbid_taxinc_gap in release 2.4.0', 'PT_excl_wagelim_rt': 'was renamed PT_qbid_w2_wages_rt in release 2.4.0', 'CTC_c_under5_bonus': 'was renamed CTC_c_under6_bonus.', 'ACTC_rt_bonus_under5family': 'was renamed ACTC_rt_bonus_under6family.', 'CTC_new_c_under5_bonus': 'was renamed CTC_new_c_under6_bonus.' } # (2) specify which Policy parameters have been redefined recently REDEFINED_PARAMS = {} # (3) specify which Policy parameters are wage (rather than price) indexed WAGE_INDEXED_PARAMS = ['SS_Earnings_c', 'SS_Earnings_thd'] def __init__(self, gfactors=None, only_reading_defaults=False, **kwargs): # put JSON contents of DEFAULTS_FILE_NAME into self._vals dictionary super().__init__() # handle gfactors argument if gfactors is None: self._gfactors = GrowFactors() elif isinstance(gfactors, GrowFactors): self._gfactors = gfactors else: raise ValueError('gfactors is not None or a GrowFactors instance') # read default parameters and initialize syr = Policy.JSON_START_YEAR lyr = Policy.LAST_BUDGET_YEAR nyrs = Policy.DEFAULT_NUM_YEARS self._inflation_rates = None self._wage_growth_rates = None self.initialize(syr, nyrs, Policy.LAST_KNOWN_YEAR, Policy.REMOVED_PARAMS, Policy.REDEFINED_PARAMS, Policy.WAGE_INDEXED_PARAMS, **kwargs)
[docs] @staticmethod def read_json_reform(obj): """ Return a reform dictionary suitable for use with implement_reform method generated from the specified JSON object, which can be None or a string containing a local filename, a URL beginning with 'http' pointing to a valid JSON file hosted online, or a valid JSON text. """ return Parameters._read_json_revision(obj, 'policy')
[docs] def implement_reform(self, reform, print_warnings=True, raise_errors=True): """ Implement reform using Tax-Calculator syled reforms/adjustments. Users may also use the adjust method with ParamTools styled reforms. """ # need to do conversion: return self._update(reform, print_warnings, raise_errors)
[docs] @staticmethod def parameter_list(): """ Returns list of parameter names in the policy_current_law.json file. """ path = os.path.join( Policy.DEFAULTS_FILE_PATH, Policy.DEFAULTS_FILE_NAME ) with open(path) as f: defaults = json.loads( # pylint: disable=protected-access return [k for k in defaults if k != "schema"]
[docs] def set_rates(self): """Initialize taxcalc indexing data.""" cpi_vals = [ vo["value"] for vo in self._data["parameter_indexing_CPI_offset"]["value"] ] # extend parameter_indexing_CPI_offset values through budget window # if they have not been extended already. cpi_vals = cpi_vals + cpi_vals[-1:] * ( self.end_year - self.start_year + 1 - len(cpi_vals) ) cpi_offset = { (self.start_year + ix): val for ix, val in enumerate(cpi_vals) } self._gfactors = GrowFactors() self._inflation_rates = [ np.round(rate + cpi_offset[self.start_year + ix], 4) for ix, rate in enumerate( self._gfactors.price_inflation_rates( self.start_year, self.end_year ) ) ] self._wage_growth_rates = self._gfactors.wage_growth_rates( self.start_year, self.end_year )