Perinatal deaths methodology

Perinatal deaths include all stillbirths and neonatal deaths. It is a legislated requirement for jurisdictional Registries of Births, Deaths and Marriages to register all stillbirths which meet the defined gestation and birth weight criteria (except for terminations in South Australia).

The definition of a stillbirth and neonatal death used for reporting within Australia is:

• A stillbirth (also referred to as a fetal death) is a death that occurs when the fetus is of 20 completed weeks or more of gestation or with a birth weight of 400 grams or more.
• A neonatal death is a death of a live born baby of any birthweight or gestation within 28 completed days of birth.

This definition differs from international reporting standards:

• The United Nations Statistics Division (UNSD) standard includes fetuses of 22 weeks or more of gestation or 500 grams, along with all neonatal deaths. A UNSD-based summary is provided in Table 9 of the data downloads.
• The World Health Organization (WHO) standard includes fetuses of 28 weeks or more of gestation or 1,000 grams, along with all neonatal deaths. A WHO-based summary is provided in Table 10 of the data downloads.

The ABS scope of perinatal death statistics includes all stillbirths and neonatal deaths received from jurisdictional Registries of Births, Deaths and Marriages (RBDMs). 

In scope:

• stillbirths of 20 weeks or more gestation or have a birth weight of 400 grams or more. 
• stillbirths with missing gestation and/or birth weight data. 
• neonatal deaths of live born babies who died with the first 28 days of life.

Out of scope:

• early pregnancy loss where both gestation and birth weight data are present, and both fall outside the scope criteria (i.e. gestation of 19 weeks or fewer and birth weight of 399 grams or fewer). 
• This scope was adopted for 2007 Perinatal deaths data and applied to historical data for 1999-2006.

 In terms of reporting on perinatal deaths:

• Stillbirths are included in the Perinatal deaths dataset only (not in scope of the Births, Deaths, or Causes of Death datasets).
• Neonatal deaths are included in the Perinatal deaths, Deaths, and Causes of Death, Australia datasets.

To register a stillbirth or a neonatal death, RBDMs require the following:

• for stillbirths, a birth notification from the hospital, birth registration statement from the family and a completed Medical Certificate of Cause of Perinatal Death (MCCPD). For some jurisdictions, a stillbirth is also registered as a death.
• for neonatal deaths, a death registration statement, usually completed by a funeral director with the family and a completed cause of death certified by either a doctor using a MCCPD or by a coroner.

Detail on the flow of information for death registrations is in the Data collection section of the Causes of Death methodology.

The scope of the collection has been expanded to include alternative data sources to better represent actual counts of stillbirths. 

• For Tasmania, stillbirths data is based on both registrations and birth notifications. 
• From 2024, Victorian stillbirths were revised back to 2020 with counts based on Medical Certificates of Cause of Perinatal Death (MCCPDs) instead of registrations. This represents a break in series for Victoria and at the Australia level. Comparisons with data prior to 2020 and in previous publications should be used with caution. Refer to Data quality - Quality considerations for use of alternative data sources for stillbirths data for more information. 

For the MCCPDs from Victoria, rules are applied so that stillbirths that meet the perinatal scope criteria are included.

The table below shows what data is currently sourced for stillbirths for each jurisdiction as at the 2025 collection.

This publication draws extensively on information provided freely by the Australian state and territory Registries of Births, Deaths and Marriages and Norfolk Island Regional Council. Their continued cooperation is very much appreciated: without it, the wide range of vital statistics published by the ABS would not be available. 

The ABS is continuing to work with RBDMs to make further improvements to the quality of ABS Perinatal deaths data.

There are a small number of stillbirth registrations provided to the ABS each year where the sex at birth has not been specified as male or female. This can be due to:

• administrative processes where the sex of the stillbirth has not been supplied to the ABS
• a clinical determination of sex not being clearly determined due to a number of reasons including extreme prematurity or some congenital conditions.

Where the sex at birth has not been specified for a stillbirth, these deaths are included in total person counts only for tabulations by fetal deaths and all perinatal deaths. 

MCCPDs for stillbirths are less likely to have a sex specified compared to stillbirths that have been registered. The use of MCCPD data for Victoria has led to an increase in the number of stillbirths where the sex has not been specified at the Victorian and Australian levels (for more detail refer to the Quality considerations for Victorian MCCPD data section in Changes to scope of ABS stillbirths collection).

Data on the Aboriginal and Torres Strait Islander origin for perinatal deaths is coded and presented in this publication based on the Indigenous Status Standard, 2014. 

Aboriginal and Torres Strait Islander perinatal death data is presented for events reported with a usual residence of New South Wales, Queensland, South Australia, Western Australia and the Northern Territory only. These jurisdictions have been found to have a higher quality of identification of Aboriginal and Torres Strait Islander origin allowing more robust analysis of data which aligns with national reporting standards. 

Due to recent improvements in the quality of Aboriginal and Torres Strait Islander status data for neonatal deaths in Victoria, and improvements to counts for Victorian stillbirths, data for this jurisdiction is also included in Table 7 in this publication for years from 2020. 

For more information about the quality of Aboriginal and Torres Strait Islander death and cause of death statistics, and changes over time, refer to the Deaths of Aboriginal and Torres Strait Islander people section of the Causes of Death methodology.

Stillbirths

For stillbirths, the derivation of Aboriginal and Torres Strait Islander origin is based on the child, mother and/or father depending on what is collected and provided by the RBDM as outlined in the table below. 

Prior to 2024, Aboriginal and Torres Strait Islander status for stillbirths registered in New South Wales was based on the Mother only. Aboriginal and Torres Strait Islander status presented in this publication is based on the Child, Mother and Father and has been revised back to 2019. Data prior to 2019 and all years published in previous Causes of Death publications should be used with caution. 

Neonatal deaths

For neonatal deaths, the Aboriginal and Torres Strait Islander origin is primarily recorded on the Death Registration Form (DRF) and the Medical Certificate of Cause of Perinatal Death (MCCPD). Aboriginal and/or Torres Strait Islander origin is derived for neonatal deaths if indicated on either the DRF or MCCPD. In cases of conflicting information, identification as an Aboriginal and/or Torres Strait Islander person is generally given preference over non-Indigenous or unknown status.

The International Classification of Diseases (ICD) is the global standard for classifying diseases and causes of death. It enables consistency in how mortality and morbidity data is recorded, interpreted and compared across countries. The classification is used for coding information from medical and death records. Currently the ICD 10th revision is used for Australian causes of death statistics.

Most perinatal deaths are coded to the following chapters:

• Chapter XVI Certain conditions originating in the perinatal period (P00-P96) 
• Chapter XVII Congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)

The ICD has been revised periodically to incorporate changes in the medical field. For further information and access to versions of the ICD refer to WHO International Classification of Diseases (ICD).

Further guidance on how causes of death are certified is available in the Cause of death certification guide. 

After a 2013 review of coding perinatal deaths, neonatal deaths were temporarily excluded from all-ages tables for underlying cause of death (refer to Changes to Perinatal Death Coding Technical Note, 2013). After consultation, a revised coding method was introduced in 2014 (retrospectively applied to 2013), using an updated Medical Certificate of Cause of Perinatal Death (MCCPD). This allowed neonatal deaths to be assigned an underlying cause, aligning their certification with general population standards and reinstating maternal conditions as underlying causes. For more information, refer to Changes to Perinatal Death Coding Technical Note in the Causes of Death, Australia, 2014.

The review resulted in fewer stillbirths and neonatal deaths where a main condition in the mother was coded as P00-P04: Fetus and newborn affected by maternal factors and by complications of pregnancy, labour and delivery. 

Neonatal deaths certified without cause details are coded as:

• P96.9 Conditions originating in the perinatal period, unspecified (if certified by a doctor). As these deaths have been certified by a doctor, the assumption is made that the neonate died of natural causes.
• R99 Other ill-defined and unspecified causes of mortality (if referred to a coroner). As a reportable death, it cannot be determined whether the neonate died of natural or external causes in the absence of further information.

For comparison and measuring purposes, perinatal deaths in this publication have also been expressed as rates. Death rates allow comparisons between populations of different sizes by expressing deaths per 1,000 births. These rates are defined as follows:

• for stillbirths (or fetal deaths) and total perinatal deaths, the rates represent the number of deaths per 1,000 all births, which comprises live births and stillbirths combined (where gestation is at least 20 weeks or birth weight is at least 400 grams).
• for neonatal deaths, the rates represent the number of deaths per 1,000 live births.

To account for processing changes impacting birth registrations in 2024, perinatal death rates for 2024 and 2025 have been calculated based on the average number of live births over the previous three years (2022-2024 for 2024, and 2023-2025 for 2025). Refer to Data quality – Live birth counts used for perinatal death rates for more details. Also refer to the Data Quality section of the methodology for other data considerations impacting on the quality of live birth counts.

Data used as the population counts for the denominator (i.e. live births and all births) are available for download in Data used to calculate perinatal death rates.

To improve the quality of mortality statistics, all coroner certified deaths are subject to a revisions process. 

For perinatal deaths, there may be minor impacts on cause information for neonatal deaths only. On average, less than 10% of neonatal deaths are referred to a coroner each year. 

Based on the current revision stages, tables include final data for 2022 and earlier, revised data for 2023, preliminary revised data for 2024 and preliminary data for 2025.

For more information on the Revisions process, refer to the Processing the data - Revisions section of the Causes of Death methodology.

Each death record includes:

• date of occurrence – when the death happened
• date of registration – when it was officially registered (if the source is a registered event)
• date received by ABS – when it was included in national statistics.

Mortality data can be reported using any of these dates.

Data in this publication is presented by year of registration except for:

• Victorian stillbirths based on MCCPDs are presented by year of receipt. Where data is presented by year of registration, for MCCPD data this corresponds to the year in which the MCCPD was received at the Victorian RBDM.
• Table 11 is presented by year of occurrence, i.e. the year the death occurred and includes all deaths the ABS received by 30 September 2026 with a date of death in 2025 or prior. 

For more detailed information about the different dates relevant to death registration and changes to how data has been presented by date over time, refer to Data release section of the Causes of Death methodology.

The Census and Statistics Act 1905 provides the authority for the ABS to collect statistical information and requires that statistical output shall not be published or disseminated in a manner that is likely to enable the identification of a particular person or organisation. This requirement may restrict access to data at a very detailed level.

Some data cells with small values have been randomly assigned to protect confidentiality. As a result, some totals will not equal the sum of their components. Cells with the value of 0 have not been affected by confidentialisation. Refer to the footnotes for the tables where confidentialisation has been applied.

Where figures have been rounded, discrepancies may occur between totals and sums of the component items.

Customised tables may be available as paid data consultancies via a Consultancy Request Form. Consultants will discuss requests to refine and ensure alignment with research objectives and data integrity standards. Requests are subject to confidentiality and quality assurance considerations.

For the full range of ABS statistical and reference information, refer to the Statistics page.

For information on upcoming releases, refer to the Release Calendar.

Not all stillbirths that occur are registered. This can be due to differences in policy and legislation of what constitutes a stillbirth and is required to be registered. Registrations may also not be finalised due to the sensitive and challenging nature of the deaths. 

The ABS has been investigating suitable alternative data sources with RBDMs to supplement the stillbirths collection. From 2024, to improve data for Victoria, the scope was expanded to include MCCPDs as the main source of stillbirths data. Data for Victoria has been revised back to 2020. For more information, refer to Data quality - Quality considerations for use of alternative data sources for stillbirths data.

Due to concerns around the undercount in the number of stillbirths for South Australia, rates for stillbirths and perinatal deaths have not been published for this jurisdiction. 

Comparison with AIHW National Perinatal Mortality Data Collection

An alternative official source of stillbirths data is held by the Australian Institute of Health and Welfare (AIHW) known as the National Perinatal Mortality Data Collection (NPMDC). AIHW data is sourced from birth notification forms completed by midwives and other birth attendants with input from family and other informants, rather than registrations and is not directly comparable to ABS data. Data from this collection is published in the AIHW Mothers and Babies report, refer to Australia’s mothers and babies: Stillbirths and neonatal deaths.

The table below compares stillbirths and neonatal deaths data from both sources. 

The move to using MCCPDs as the primary source of information for stillbirths rather than registrations provides a more accurate count of stillbirths for Victoria. This has an impact at both the Victorian and Australian levels. For more detail on the impact of using MCCPDs for stillbirths in Victoria refer to Changes to scope of ABS stillbirths collection.

Other quality considerations include: 

• Unregistered stillbirths were more likely to be of lower gestational age with a higher proportion of pregnancy terminations.
• MCCPD for stillbirths are timelier due to jurisdictional requirements to be completed and submitted to the Registrar within 48 hours to 10 days.
• MCCPDs for stillbirths are more likely to not have a sex specified compared to stillbirths that have been registered. This has increased the number of stillbirths where the sex has not been specified as male or female at the Victorian and Australian levels. The ABS will continue to work with the Victorian Registry to better understand the quality of the sex information on the MCCPDs.
• Stillbirths data by Aboriginal and Torres Strait Islander origin has not previously been published for Victoria due to quality concerns. This data has now been included in tables with data from 2020. The derivation of this data is based on the status of the Mother and Father as provided on the MCCPD only.

Prior to 2023, the ‘registration date’ for Tasmanian stillbirths was based on the date the stillbirth was first entered into the registry system (the insertion date), rather than the date on which the registration was finalised (the registration date). From 2023, where available, the registration date has been used, aligning reporting for all jurisdictions. For notifications of stillbirths that were not yet registered as at the time of finalising data for the reference period, the registration date is set to the reference year.

The number of births registered from year to year can be impacted by administrative factors such as processing times. To account for larger movements in 2024 and 2025, the denominator for perinatal death rates has been calculated based on the average number of registered live births over the previous three years (2023-2025). More detail on factors influencing annual birth registration counts at the state and territory level is available in the Births, Australia methodology. This includes historical considerations impacting other years.

From 2024, a methodological change (an additional field of information on Aboriginal and Torres Strait Islander births) was applied by the ABS when deriving Aboriginal and Torres Strait Islander origin for births registered in four jurisdictions: New South Wales, Western Australia, Tasmania and the Northern Territory. This has resulted in an increase in the number of births where the infant was identified as being of Aboriginal and Torres Strait Islander origin.

Refer to Change in how Indigenous status of births is derived in the Births, Australia, 2024 methodology for further information.

In 2023, Tasmania recorded a 1.3% increase in births (69 more than in 2022), largely due to a change in how birth registrations are processed. From January 2023, births are now assigned to a reference year based on the registration date rather than the insertion date into the registry system. This aligns Tasmania with other jurisdictions. As a result, 336 births that would have been counted in 2022 were instead included in 2023, accounting for nearly two-thirds (63.5%) of the decrease in Tasmania's 2022 births. All Tasmanian births continue to be registered and reported to the ABS.

Aboriginal and/or Torres Strait Islander person

A person who identified as being of Aboriginal and/or Torres Strait Islander origin. The Aboriginal and Torres Strait Islander origin of deceased persons is captured through administrative processes at the Registries of Births, Deaths and Marriages. For further information refer to the Classifications - Aboriginal and Torres Strait Islander origin section.

All births

All births comprises all live births plus all stillbirths (i.e. fetal deaths with a gestation at least 20 weeks or birth weight at least 400 grams) for a specific year. This is the denominator used in calculating perinatal death rates and stillbirth rates in this publication. 

For data tables pertaining to international standards, the definition of all births is:

• for the United Nations Statistics Division definition, all births comprises all live births plus all fetal deaths with gestation of at least 22 weeks or a birth weight of at least 500 grams, and
• for the World Health Organization definition, all births comprises all live births plus all fetal deaths with gestation of at least 28 weeks or a birth weight of at least 1,000 grams. 

Cause of death

The causes of death to be entered on the Medical Certificate of Cause of Death or Medical Certificate of Cause of Perinatal Death are all those diseases, morbid conditions or injuries that either resulted in or contributed to death and the circumstances of the accident or violence that produced any such injuries.

Certifier type

Deaths may be certified by either a medical practitioner, using the Medical Certificate of Cause of Death or Medical Certificate of Cause of Perinatal Death (doctor certified), or coroner (coroner certified). Natural causes are predominantly certified by doctors, whereas external and unknown causes are usually certified by a coroner. However, some deaths for natural causes are referred to coroners for investigation, for example, unaccompanied deaths.

Confidentialised

Some data cells with small values have been randomly assigned to protect confidentiality. As a result some totals will not equal the sum of their components. Cells with 0 values have not been affected by confidentialisation. Refer to the footnotes for the tables where confidentialisation has been applied.

Coroner certified deaths

Deaths that were certified by a coroner. Coroner cases remain open while cause of death investigations are undertaken, and are closed when coronial investigations are complete. Following completion, causes of death information is passed to the Registry of Births, Deaths and Marriages, as well as to the National Coronial Information System (NCIS). All coroner certified deaths are subject to a revision process. 

Data cubes

Data cubes are a series of spreadsheets which present the perinatal deaths data. Perinatal death data cubes can be found in Perinatal deaths under the Data downloads section.

Death

Death is the permanent disappearance of all evidence of life after birth has taken place. The definition excludes all deaths prior to live birth. For the purposes of the Deaths, Causes of Death and Perinatal Deaths collections, a death refers to any death that occurs in, or en route to, Australia and is registered with a state or territory Registry of Births, Deaths and Marriages.

Doctor certified deaths

Deaths that were certified by a doctor or medical practitioner, which were not required to be referred on to a coroner. Doctor certified deaths are not subject to the revisions process.

Early neonatal death

Death of a live born baby within seven days of birth.

Fetal death

A fetal death is a death of a fetus prior to the complete expulsion or extraction from its mother as a product of conception. If the death occurs when the fetus is of at least 20 completed weeks of gestation or with a birth weight of at least 400 grams. For the purposes of this publication, the terms fetal death and stillbirth have been used interchangeably. 

For data tables pertaining to international standards:

• the United Nations Statistics Division definition, a fetal death is defined as one with a gestation of at least 22 weeks or a birth weight of at least 500 grams, and
• the World Health Organization definition, a fetal death is defined as one with a gestation of at least 28 weeks or a birth weight of at least 1,000 grams. 

​​​​​​​Fetal death rate

The number of fetal deaths in a registration year per 1,000 all births (live births plus fetal deaths of relevant scope) in the same year. Refer to 'All births' above.

ICD

International Statistical Classification of Diseases and Related Health Problems. The purpose of the ICD is to permit the systematic recording, analysis, interpretation and comparison of mortality and morbidity data collected in different countries or areas and at different times. The ICD, which is endorsed by the World Health Organization (WHO), is primarily designed for the classification of diseases and injuries with a formal diagnosis. The ICD-10 is the current classification system, which is structured using an alphanumeric coding scheme. Each disease or health problem listed on the death certificate is assigned a 3-character identification code. Causes of death statistics can be produced for aggregates of these, for example, chapter level (letter), 2-character code (first two characters of the assigned code), and 3-character code (first three characters of the assigned code). 

Late neonatal death

Death of a live born baby after seven completed days and within 28 completed days of birth.

Live births

A live birth is the complete expulsion or extraction of a child from its mother as a product of conception, irrespective of the duration of pregnancy, which after such separation, breathes or shows any other evidence of life, such as beating of the heart, pulsation of the umbilical cord or definite movement of voluntary muscles, whether or not the umbilical cord has been cut or the placenta is attached; each product of such a birth is considered live born. This is the denominator used in calculating neonatal death rates in this publication, and contributes to the denominator used for calculating stillbirth and total perinatal death rates.

Mortality

Refer to 'Death'.

Neonatal death

A neonatal death is death of a live born baby within 28 completed days of birth.

Neonatal death rate

The number of deaths in a registration year of live born babies within 28 completed days of birth per 1,000 live births in the same reference year.

Neonatal period

The neonatal period commences at birth and ends 28 completed days after birth.

Other territories

Following the 1992 amendments to the Acts Interpretation Act, the Indian Ocean Territories of Christmas Island and the Cocos (Keeling) Islands are included as part of geographic Australia. As of 01 July, 2016, Norfolk Island is now also considered part of geographic Australia, due to the introduction of the Norfolk Island Legislation Amendment Act 2015. Jervis Bay Territory (previously included with the Australian Capital Territory), Christmas Island, the Cocos (Keeling) Islands and Norfolk Island appear as "Other Territories", which is another category that has been created at the same level as states and territories within the Australian Statistical Geography Standard (ASGS).

Perinatal death

A death that is either a stillbirth (i.e. a fetal death prior to the complete expulsion or extraction from its mother as a product of conception of 20 completed weeks of gestation or with a birth weight of at least 400 grams, or a neonatal death (i.e. death of a live born baby within 28 completed days of birth).

For data tables pertaining to international standards:

• the United Nations Statistics Division definition, a perinatal death comprises all neonatal deaths plus all fetal deaths with gestation of at least 22 weeks or a birth weight of at least 500 grams, and
• the World Health Organization definition, a perinatal death comprises all neonatal deaths plus all fetal deaths with gestation of at least 28 weeks or a birth weight of at least 1,000 grams. 

Perinatal death rate

Perinatal death rates are the number of perinatal deaths in a registration year (i.e. stillbirths and neonatal deaths) per 1,000 all births in the same reference year. Refer to 'All births'.

Perinatal period

The perinatal period commences at 20 weeks of gestation and ends within 28 completed days of birth.

Period of gestation

Period of gestation is measured from the first day of the last normal menstrual period to the date of birth and is expressed in completed weeks.

Post neonatal death

Death of a live born baby after 28 days and within one year of birth.

Rate difference

Rate difference is calculated by subtracting the standardised death rate for one group (such as all persons with a usual residence of Queensland) from the standardised death rate for the total relevant population (such as all persons with a usual residence of Australia).

Rate ratio

Rate ratio is calculated by dividing the standardised death rate for one group (such as all persons with a usual residence of Queensland) by the standardised death rate for the total relevant population (such as all persons with a usual residence of Australia).

Reference year

Data for a particular reference year includes all deaths registered in Australia for the reference year that are received by the ABS by the end of the March quarter of the subsequent year. For example, data for the 2025 reference year includes all deaths registered in Australia in 2025 that was received by the ABS by the end of March 2026. Data for the ABS Deaths, Australia publication is presented by reference year.

Registration year

Perinatal deaths data is presented on a year of registration basis unless otherwise specified. This relates to the date the death was registered with the relevant jurisdictional Registry of Births, Deaths and Marriages. 

Registry of Births, Deaths and Marriages

Each state and territory has a Registry of Births, Deaths and Marriages. It is a legal requirement that all deaths are recorded by the relevant Registry for the state or territory in which the death occurred. Deaths registered by the Norfolk Island Registry of Births, Deaths and Marriages are also included in the death statistics for Australia. 

Reportable deaths

Deaths which are reported to a coroner.

Revisions process

When additional information about an 'open' coroner certified death is received by the ABS, a more specific ICD-10 code may be applied, thereby 'revising' the cause of death. Refer to Revisions process in the Processing the data - Revisions process section of the methodology for further information.

Sex not specified

Sex not specified refers to stillbirths where the deceased has not been specified as male or female. Stillbirths where sex is not specified are included in person totals for data presented for stillbirths and perinatal deaths.

State or territory of registration

State or territory of registration refers to the state or territory in which the death was registered. It is the state or territory in which the death occurred, but is not necessarily the deceased's state or territory of usual residence. Deaths registered by the Norfolk Island Registry of Births, Deaths and Marriages are not counted in any Australian state or territory of registration but are included in the Australian totals.

State or territory of usual residence

State or territory of usual residence refers to the state or territory in which the deceased usually resided. Deaths registered by the Norfolk Island Registry of Births, Deaths and Marriages are presented by the state or territory in which the deceased usually resided. If the deceased normally resided on Norfolk Island, these deaths are counted in the category of “Other territories” and are included in the Australian totals. 

Stillbirth

A stillbirth (also referred to as a fetal death in this publication) is a death prior to the complete expulsion or extraction from its mother as a product of conception of at least 20 completed weeks of gestation or with a birth weight of at least 400 grams. The death is indicated by the fact that after such separation the fetus does not breathe or show any other evidence of life, such as beating of the heart, pulsation of the umbilical cord, or definite movement of voluntary muscles. 

For data tables pertaining to international standards:

• the United Nations Statistics Division definition, a stillbirth is defined as one with a gestation of at least 22 weeks or a birth weight of at least 500 grams, and
• the World Health Organization definition, a stillbirth is defined as one with a gestation of at least 28 weeks or a birth weight of at least 1,000 grams.

Underlying cause of death

The disease or injury that initiated the train of morbid events leading directly to death. Accidental and violent deaths are classified according to the external cause, that is, to the circumstances of the accident or violence which produced the fatal injury rather than to the nature of the injury.

Unknown cause of death

Deaths for which it is not possible to determine between a natural and an external cause.

Year of occurrence

Data presented on a year of occurrence basis relates to the date the death occurred rather than when it was registered with the relevant state or territory Registry of Births, Deaths and Marriages.