model_income_tax: Modelled Income Tax

In grattan: Australian Tax Policy Analysis

Modelled Income Tax

Description

The income tax payable if tax settings are changed.

Usage

model_income_tax(
  sample_file,
  baseline_fy,
  elasticity_of_taxable_income = NULL,
  ordinary_tax_thresholds = NULL,
  ordinary_tax_rates = NULL,
  medicare_levy_taper = NULL,
  medicare_levy_rate = NULL,
  medicare_levy_lower_threshold = NULL,
  medicare_levy_upper_threshold = NULL,
  medicare_levy_lower_sapto_threshold = NULL,
  medicare_levy_upper_sapto_threshold = NULL,
  medicare_levy_lower_family_threshold = NULL,
  medicare_levy_upper_family_threshold = NULL,
  medicare_levy_lower_family_sapto_threshold = NULL,
  medicare_levy_upper_family_sapto_threshold = NULL,
  medicare_levy_lower_up_for_each_child = NULL,
  lito_max_offset = NULL,
  lito_taper = NULL,
  lito_min_bracket = NULL,
  lito_multi = NULL,
  offsets = NULL,
  Budget2018_lamington = FALSE,
  Budget2019_lamington = NA,
  Budget2018_lito_202223 = FALSE,
  Budget2018_watr = FALSE,
  Budget2019_watr = FALSE,
  sapto_eligible = NULL,
  sapto_max_offset = NULL,
  sapto_lower_threshold = NULL,
  sapto_taper = NULL,
  sapto_max_offset_married = NULL,
  sapto_lower_threshold_married = NULL,
  sapto_taper_married = NULL,
  sbto_discount = NULL,
  cgt_discount_rate = NULL,
  calc_baseline_tax = TRUE,
  return. = c("sample_file", "tax", "sample_file.int"),
  clear_tax_cols = TRUE,
  warn_upper_thresholds = TRUE,
  .debug = FALSE
)

Arguments

sample_file	A sample file having at least as many variables as the 2012-13 sample file.
baseline_fy	If a parameter is not selected, the parameter's value in this tax year is used. Must be a valid tax year and one for which income_tax has been programmed.
elasticity_of_taxable_income	Either NULL (the default), or a numeric vector the same length of sample_file (or length-1) providing the elasticity of taxable income for each observation in sample_file; \frac{\Delta z / z}{\Delta \tau / (1 - \tau)} where z is taxable income and \tau is tax payable. For example, if, for a given taxpayer, the tax settings would otherwise result in a 2% decrease of disposable income under the tax settings to be modelled, and elasticity_of_taxable_income is set to 0.1, the Taxable_Income is reduced by 0.2% before the tax rates are applied. If NULL, an elasticity of 0 is used.
ordinary_tax_thresholds	A numeric vector specifying the lower bounds of the brackets for "ordinary tax" as defined by the Regulations. The first element should be zero if there is a tax-free threshold.
ordinary_tax_rates	The marginal rates of ordinary tax. The first element should be zero if there is a tax-free threshold. Since the temporary budget repair levy was imposed on a discrete tax bracket when it applied, it is not included in this function.
medicare_levy_taper	The taper that applies between the _lower and _upper thresholds.
medicare_levy_rate	The ordinary rate of the Medicare levy for taxable incomes above medicare_levy_upper_threshold.
medicare_levy_lower_threshold	Minimum taxable income at which the Medicare levy will be applied.
medicare_levy_upper_threshold	Minimum taxable income at which the Medicare levy will be applied at the full Medicare levy rate (2% in 2015-16). Between this threshold and the medicare_levy_lower_threshold, a tapered rate applies, starting from zero and climbing to medicare_levy_rate.
medicare_levy_lower_sapto_threshold, medicare_levy_upper_sapto_threshold	The equivalent values for SAPTO-eligible individuals (not families).
medicare_levy_lower_family_threshold, medicare_levy_upper_family_threshold	The equivalent values for families.
medicare_levy_lower_family_sapto_threshold, medicare_levy_upper_family_sapto_threshold	The equivalent values for SAPTO-eligible individuals in a family.
medicare_levy_lower_up_for_each_child	The amount to add to the _family_thresholds for each dependant child.
lito_max_offset	(deprecated) The maximum offset available for low incomes.
lito_taper	(deprecated) The taper to apply beyond lito_min_bracket.
lito_min_bracket	(deprecated) The taxable income at which the value of the offset starts to reduce (from lito_max_offset).
lito_multi	No longer supported.
offsets	A list of lists created by set_offsets. If NULL, the default, the list is populated by the offsets in baseline_fy.
Budget2018_lamington	No longer supported
Budget2019_lamington	No longer supported.
Budget2018_lito_202223	No longer supported.
Budget2018_watr	No longer supported
Budget2019_watr	No longer supported.
sapto_eligible	Whether or not each taxpayer in sample_file is eligible for SAPTO. If NULL, the default, then eligibility is determined by age_range in sample_file; i.e., if age_range <= 1 then the taxpayer is assumed to be eligible for SAPTO.
sapto_max_offset	The maximum offset available through SAPTO.
sapto_lower_threshold	The threshold at which SAPTO begins to reduce (from sapto_max_offset).
sapto_taper	The taper rate beyond sapto_lower_threshold.
sapto_max_offset_married, sapto_lower_threshold_married, sapto_taper_married	As above, but applied to members of a couple
sbto_discount	The tax_discount in small_business_tax_offset.
cgt_discount_rate	(numeric(1)) The capital gains tax discount rate, currently 50%.
calc_baseline_tax	(logical, default: TRUE) Should the income tax in baseline_fy be included as a column in the result?
return.	What should the function return? One of tax, sample_file, or sample_file.int. If tax, the tax payable under the settings; if sample_file, the sample_file, but with variables tax and possibly new_taxable_income; if sample_file.int, same as sample_file but new_tax is coerced to integer.
clear_tax_cols	If TRUE, the default, then return. = sample_file implies any columns called new_tax or baseline_tax in sample_file are dropped silently.
warn_upper_thresholds	If TRUE, the default, then any inconsistency between baseline_fy and the upper thresholds result in a warning. Set to FALSE, if the lower_thresholds may take priority.
.debug	Return a data.table of new_tax. Experimental so cannot be relied in future versions.

Examples

library(data.table)
library(hutils)

# With new tax-free threshold of $20,000:
# if (requireNamespace("taxstats", quietly = TRUE) && FALSE) {
# library(taxstats)
# library(magrittr)
#    
# model_income_tax(sample_file_1314,
#                  "2013-14",
#                  ordinary_tax_thresholds = c(0, 20e3, 37e3, 80e3, 180e3)) %>%
 #   select_grep("tax", "Taxable_Income")
#
# }

grattan documentation built on Sept. 4, 2023, 5:08 p.m.