Australian Tax Policy Analysis.
grattan
Utilities for costing and evaluating Australian tax policy, including high-performance tax and transfer calculators, a fast method of projecting tax collections from ATO sample files, and an interface to common indices from the Australian Bureau of Statistics. Written to support Grattan Institute’s Australian Perspectives program.
Overview
install.packages("grattan")
library(grattan)
income_tax
Calculates the income tax for a given taxable income and financial year:
income_tax(50e3, "2015-16")
## [1] 8547
With sample files
income_tax
is designed to work well with the ATO’s sample files. You can obtain the sample files from my repo:
# install.packages("taxstats", repos = "https://hughparsonage.github.io/tax-drat")
library(taxstats)
library(hutils)
library(data.table)
library(magrittr)
library(ggplot2)
Simply pass the sample file to .dots.ATO
and the complexities of things like Medicare levy and the Seniors and Pensioners Tax Offset are handled for you. For example:
s1314 <- as.data.table(sample_file_1314)
s1314 %>%
.[, tax := income_tax(Taxable_Income, "2013-14", .dots.ATO = s1314)] %>%
.[, .(Taxable_Income, tax)]
## Taxable_Income tax
## 1: 4800 0.000
## 2: 126122 36503.970
## 3: 39742 4655.410
## 4: 108123 29574.355
## 5: 85957 21040.445
## ---
## 258770: 24462 1111.710
## 258771: 37055 3701.525
## 258772: 45024 6530.520
## 258773: 5134 0.000
## 258774: 46368 7007.640
model_income_tax
: modelling changes to personal income tax
While income_tax
is designed to inflexibly return the tax payable as legislated, model_income_tax
is designed to calculate income tax when changes are made. For example,
s1314 %>%
# reduce top threshold from 180,000 to 150,000
model_income_tax(ordinary_tax_thresholds = c(0, 18200, 37000, 80000,
150e3),
baseline_fy = "2013-14") %>%
.[, .(Taxable_Income, baseline_tax, new_tax)]
## Taxable_Income baseline_tax new_tax
## 1: 4800 0.000 0.000
## 2: 126122 36503.970 36503.970
## 3: 39742 4655.410 4655.410
## 4: 108123 29574.355 29574.355
## 5: 85957 21040.445 21040.445
## ---
## 258770: 24462 1111.710 1111.710
## 258771: 37055 3701.525 3701.525
## 258772: 45024 6530.520 6530.520
## 258773: 5134 0.000 0.000
## 258774: 46368 7007.640 7007.640
project
Given a sample file, we can project forward a number of years
s1617 <- project(s1314, h = 3L)
or to a particular financial year
s1718 <- project_to(s1314, "2017-18")
Together with model_income_tax
, this allows us to make point-predictions of future years. The function revenue_foregone
prettily prints the resultant revenue:
sample_file_1314 %>%
project_to("2018-19") %>%
model_income_tax(baseline_fy = "2017-18",
ordinary_tax_thresholds = c(0, 18200, 37000, 87000,
150e3)) %>%
revenue_foregone
## [1] "$1.7 billion"
compare_avg_tax_rates
:
Create comparison of average tax rates:
lapply(list("30k" = 30e3,
"36k" = 36e3,
"42k" = 42e3),
function(T2) {
model_income_tax(s1718,
baseline_fy = "2017-18",
ordinary_tax_thresholds = c(0,
18200,
T2,
87000,
180e3))
}) %>%
rbindlist(idcol = "id",
use.names = TRUE,
fill = TRUE) %>%
compare_avg_tax_rates(baseDT = .[id %ein% "36k"]) %>%
ggplot(aes(x = Taxable_Income_percentile,
y = delta_avgTaxRate,
color = id,
group = id)) +
geom_hline(yintercept = 0) +
geom_line()
## Warning: Removed 6 row(s) containing missing values (geom_path).
NEWS
2023.0
_inflator
functions have been moved to grattanInflator, breaking (for example)cpi_inflator_general_date
which are nowcpi_inflator
.
2.0.0.0
Breaking changes
income_tax
no longer acceptsfamily_status
,n_dependants
,allow.forecasts
and.debug
model_income_tax
Arguments prefixedBudget_
andlito_
are deprecated and nowoffsets = set_offsets
are preferred. However, usingSystem
withincome_tax
is likely to be just as convenient.lito
andlmito
no longer accept varying parameters, butlmito
is now exportedsapto_rcpp
,income_tax_sapto
,new_income_tax
,new_medicare_levy
, andnew_sapto
have now been removed. UseSystem
.The transfer functions have been removed as they became unreliable / difficult to maintain. See repository
hughparsonage/grattanTransfers
for possible future developmentage_pension
carer_payment
child_care_subsidy
energy_supplement
family_tax_benefit
model_child_care_subsidy
model_rent_assistance
newstart_allowance
pension_supplement
rent_assistance
student_repayment
unemployment_benefit
youth_allowance
youth_unemployment
The
grattan v2
package will be more focused on income tax with other elements being spun off into other packages. In particular,_inflator
functions and related forecasting methods, functions essentially accessing ABS data, and functions relating to tranfers will be put in other packages, and imported later. Functions that are made available in thegrattan
NAMESPACE may have changes to their API when this happens.
API changes
income_tax
now usesSystem
to define the tax system
Other changes
model_income_tax
does not throw an error for incorrect specification oflito_
arguments (which are deprecated)age_grouper
now works with long vectors containing missing values
1.9.0.10
- New data changes to 2022
rent_assistance()
example no longer works because of outdated data.
Breaking changes anticipated in 2.0.0.0
income_tax
andmedicare_levy
no longer acceptfamily_status
as an input, since it was giving misleading results. Use.dots.ATO
with appropriate variables to define the spouse’s income or the number of children.income_tax
gives a slightly different error message when an invalid financial year is passed. Previously “not in correct form”, now “not a valid financial year”.useABSConnection = TRUE
is no longer supported because of ABS server issues
1.9.0.8
- Maintenance release for the new financial year.
1.9.0.0
New features
- 2017-18 sample file now contemplated as an input to
project
project
now hasr_super_balance
to project super balances by a user-supplied factor, rather than a hard-coded 1.05.- Modelling superannuation changes now accepts contributions taxes relative to marginal rates.
Data
- Data updated to 2020-06-30
Internal:
package:rsdmx
is now Suggested, since a dependency has been orphaned.
1.8.0.1
Bug fixes
- Fixed issue with stringsAsFactors = FALSE being inconsistently applied with R 4.0
Data
- Update wage, CPI, and labour force data
1.7.1.4
- Fixed minor error that affected tax liability calculations for 2010-11 and 2011-12 financial years
1.7.1.3
grattan
’s tax modelling functions now work with the 2016-17 ATO sample file
1.7.1.1
grattan
now depends on R 3.5.0 due to serialization format version 3 becoming the default in R 3.6.0.cpi_inflator
fails more gracefully when the ABS’s website is not available
1.7.1.0
Bug fixes
income_tax
now gives consistent results modulo the existence of completely empty columns that are inputs forsapto
(#158)income_tax
will work if.dots.ATO
is a non-data.table data.frame.model_income_tax
:- Correctly imputes SAPTO vs non-SAPTO family thresholds when both provided.
sapto_rcpp
is now more careful about passing length-one vectors to vectorized C++ functions.
project
now correctly prioritizesexcl_vars
over variables with otherwise predefined uprating mechanisms (such asSw_amt
).
New functions:
awote
for weekly earnings
Enhancements:
age_grouper
can now have a custom first label prefix, and is much faster whenlength(age)
is large.income_tax
now emits a warning when both age and.dots.ATO
are provided, indicating thatage
will be ignored.- The data has been updated to 2019-02-23.
Internal
mutate_ntile
andweighted_ntile
now use thehutils
equivalents. This broke 3 unit tests because of the specific phrasing of some error messages.- The vignette requires pandoc > 2.4. Some chunks have been refactored to avoid excess memory usage.
1.7.0.0
Bug fixes
- Fixed failing interaction between temporary budget repair levy and small business tax offset in 2016-17.
small_business_tax_offset()
is now always positive, fixing the original misinterpretation of the legislation whereby negative business income resulted in a negative offset.*_inflator
functions now return correct results for non-standard but supported financial years.inflator
no longer fails whento_fy
is length > 1 and unordered.
New features
mutate_ntile
andmutate_weighted_ntile
for adding quantile columns- New welfare functions (usable for the 2015-16 financial year)
age_pension
,carer_payment
carers_allowance
energy_supplement
family_tax_benefit
newstart_allowance
pension_supplement
rent_assistance
the Commonwealth Rent Assistancemodel_rent_assistance
as experimental function for modelling changes to rent assistance.youth_allowance()
now available, though limited
compare_avg_tax_rates
: create a difference in average tax rates between multiple models and a baseline tax, by percentile.install_taxstats()
as a convenient means to install the non-CRANtaxstats
dependency.
Enhancements
prohibit_vector_recycling()
and friends return more informative error messages.- Added default values to the following functions:
income_tax
,income_tax_sapto
: the default value for fy.year is the current financial yearcpi_inflator
,lf_inflator_fy
,wage_inflator
: if both from_fy and to_fy are missing, the default values become the previous and current financial years respectively. If only one of the two are missing, an error appears.
income_tax
is about twice as fast since 1.6.0.0: 1.5-2.0s down from 3.0-3.7s on the 100% population (13 million)inflator
andcpi_inflator
,lf_inflator_fy
, andwage_inflator
are now much faster when eitherfrom_fy
orto_fy
have more than 100,000 elements:
set.seed(19952010)
from_fys <- sample(yr2fy(1995:2010), size = 1e6, replace = TRUE)
microbenchmark(cpi_inflator(from_fy = from_fys, to_fy = "2015-16"))
# Old
Unit: seconds
expr min lq mean median uq
cpi_inflator(from_fy = from_fys, to_fy = "2015-16") 1.519483 1.54438 1.550628 1.549735 1.554507
max neval
1.661502 100
# New
Unit: milliseconds
expr min lq mean median uq
cpi_inflator(from_fy = from_fys, to_fy = "2015-16") 40.71753 41.94061 47.93162 42.93946 48.08461
max neval
191.3497 100
Potentially breaking changes
yr2fy(x)
no longer works for x = 1900L, despite a unit test, for the sake of performance.
#> Last change: NAMESPACE at 2018-08-19 14:47:14 (4 mins ago).
#> Unit: milliseconds
#> expr min lq mean median uq max neval cld
#> yr2fy(z) 75 88 98 90 101 161 100 a
#> .yr2fy(z) 274 286 298 297 302 359 100 b
Use yr2fy(x, assume1901_2100 = FALSE)
if you need the old behaviour.
Misc/Internal
taxstats1516
is now a suggested dependency.
1.6.0.0
2018-05-08
- Never-legislated Medicare levy change in 2019-20 has been reverted
- Budget 2018:
model_income_tax()
no longer coercesWEIGHT
to integer.- New arguments to support Budget 2018:
lito_multi
Permits multiple pieces to the linear offset.Budget2018_lamington
The Low And Middle Income Tax Offset proposed in the Budget 2018 budget.Budget2018_lito_202223
The proposed change to LITO from 2022-23.Budget2018_watr
The offset proposed by the Opposition the Budget Reply.sbto_discount
Allows modification of the small business tax offset.clear_tax_cols
By default, old tax columns are deleted.warn_upper_thresholds
If changed toFALSE
allows the automatic changes to be applied without warning.
- New functions:
progressivity()
for Gini-based measure of the progressivity of income taxrevenue_foregone()
as a convenenience for returning the revenue foregone from a modelled sample file.
- Routine changes:
- ABS data updated as of 2018-05-21.
1.5.3.6
2018-02-21
- Labour force data and wage price index updated to 2018-02-21.
- Update as requested to fix failing unit tests relying on non-standard packages.
1.5.3.1
2018-01-22
New features:
- New function
model_income_tax
which attempts to provide every lever of the income tax system that is visible from the tax office’s sample files. Users can model the sample file by changing single parameters to observe the effect on tax collections. small_business_tax_offset
: Include the small business tax offset as a standalone function and withinincome_tax
.
Other user-visible changes
project
andproject_to
no longer requirefy.year.of.sample.file
. However, they expect the supplieddata.frame
to be compatible with the sample file provided. Failling to provide a sample file with the expected number of rows or not providing a sample file with a valid number of rows is a warning, which can be silenced bycheck_fy_sample_file = FALSE
.
Data:
- Update labour force data to November 2017
- Internal projection tables have been updated for the latest (2014-15) sample file.
Other changes
mgcv
was used but not declared in Suggests: Thanks to BDR for reporting.- (internal) Extend
prohibit_vector_recycling
to return the maximum permissible length of a list of vectors.
1.5.2.5
2017-11-16
- Update wage data to 2017-Q3
- Update labour force data to 2017-09
- (internal) The
lf_trend
internal data table used to report the labour force in thousands of persons, as the ABS does. This seemed a bit strange, so nowobsValue
uses integers (i.e. just the labour force). - Vignettes now install
taxstats
to a temporary directory if not already installed, rather than the user or system’s library.
2017-10-27
- Update CPI data
- Fix wage data
1.5.2.3
2017-10-21
- Update labour-force data
1.5.2.0
2017-10-19
- New internal C++ functions for
income_tax
, and related functions - BTO function now uses tax scales from the Income Tax Regulations
1.5.1.2
2017-10-15
- Optional argument
age
inincome_tax
nowNULL
rather than42
.
The default argument continues to result in SAPTO being not applied if.dots.ATO
. However, if.dots.ATO
is supplied (and the age variable has not been removed from it), the individuals’ SAPTO eligibility is determined by the age variable in.dots.ATO
, rather than setting each individual’s SAPTO to 0.
2017-08-30
- Update labour force data. Avoid segfault in separate package in unit test.
- Added a
NEWS.md
file to track changes to the package.
2017-08-16
- Update wage, CPI, labour force data
2017-07-02
- Update wage and labour force data
- Fix breaking build due to change in dplyr API
CRAN Notes
This is a package update
Test results
0 ERRORS | 0 WARNINGS | 1-2 NOTEs
NOTES:
Notes for taxstats are routine.