# Historical savings/deposit-rate research

Snapshot: 2026-09-15. Default: the user's annual savings interest rate stays constant. Moving out of stocks means moving into interest-bearing savings, not holding physical currency.

## Optional replay

The option applies **percentage-point changes**, not the historical absolute rate: modeled rate = max(0, user rate + historical rate − historical rate at crash onset). The rate stays constant before the future crash starts. Only the crash world replays rate changes; the no-crash counterfactual keeps the user rate constant. These are modeling assumptions, not causal estimates or interest-rate forecasts. A 2-point historical fall takes a user rate of 2.5% to 0.5%, not to the original historical rate.

Rates are selected by the crash market. This assumes the savings rate responds like that market's local deposit rates, even though the portfolio is displayed in euros. No foreign-currency conversion, inflation, tax, account fees, access restrictions, bank failure or deposit-guarantee mechanics are modeled.

The integration splits every interval at rate-change dates and compounds each segment as (1 + annual rate / 100)^(elapsed months / 12). This treats quoted annual rates as effective annual yields for the scenario, an approximation for sources that quote nominal per-annum rates. Annual observations apply to their full calendar year retrospectively; monthly/weekly observations are held to the next observation. Annual data cannot resolve a reaction in a particular week or month and are not a point-in-time investable backtest.

A missing onset baseline disables the historical option. A gap or exhausted series ends observed coverage; beyond it the **last modeled rate is held constant**, explicitly an assumption, not measured historical data. Never backfill a missing onset from later observations.

## Coverage

| Scenario | Option | Source | Frequency | Starting → last covered historical rate / limitation |
| --- | --- | --- | --- | --- |
| 1929 · Wall Street crash · United States | Unavailable | [FDIC national non-jumbo savings rate](https://fred.stlouisfed.org/series/SAVNRNJ) | Weekly | The verified weekly series does not cover the crash onset (1929-09-07). |
| 1973 · Oil shock & stagflation · United States | Unavailable | [FDIC national non-jumbo savings rate](https://fred.stlouisfed.org/series/SAVNRNJ) | Weekly | The verified weekly series does not cover the crash onset (1973-01-11). |
| 1987 · Black Monday · United States | Unavailable | [FDIC national non-jumbo savings rate](https://fred.stlouisfed.org/series/SAVNRNJ) | Weekly | The verified weekly series does not cover the crash onset (1987-08-25). |
| 1987 · Hong Kong market crash · Hong Kong | Unavailable | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=HKG) | Annual | The verified annual series does not cover the crash onset (1987-10-01). |
| 1989 · Japanese asset bubble · Japan | Available (partial history) | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=JPN) | Annual | 3.08% → 0.32% (through 2018-01-01) |
| 1994 · Mexican peso crisis · Mexico | Available | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=MEX) | Annual | 15.03% → 26.40% (through 1996-01-02) |
| 1997 · Asian crisis in Korea · South Korea | Available | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=KOR) | Annual | 10.80% → 7.95% (through 1999-04-27) |
| 1997 · Asian crisis in Thailand · Thailand | Available (partial history) | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=THA) | Annual | 10.52% → 2.54% (through 2002-01-01) |
| 1997 · Asian crisis in Indonesia · Indonesia | Available | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=IDN) | Annual | 20.01% → 6.44% (through 2004-01-09) |
| 1999 · Greek bubble & debt crisis · Greece | Unavailable | No verified matching series | — | No suitable deposit/savings series verified for this market and era. |
| 2000 · Dot-com bubble · United States | Unavailable | [FDIC national non-jumbo savings rate](https://fred.stlouisfed.org/series/SAVNRNJ) | Weekly | The verified weekly series does not cover the crash onset (2000-03-10). |
| 1999 · UK millennium peak · United Kingdom | Available | [Bank of England historical bank deposit rate](https://fred.stlouisfed.org/series/BDRUKM) | Monthly | 2.53% → 0.76% (through 2015-02-24) |
| 2000 · French dot-com bubble · France | Available (partial history) | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=FRA) | Annual | 2.63% → 0.79% (through 2018-01-01) |
| 2007 · Chinese equity bubble · China | Available (partial history) | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=CHN) | Annual | 4.14% → 1.50% (through 2025-01-01) |
| 2007 · Global financial crisis · United States | Unavailable | [FDIC national non-jumbo savings rate](https://fred.stlouisfed.org/series/SAVNRNJ) | Weekly | The verified weekly series does not cover the crash onset (2007-10-09). |
| 2008 · Global crisis in India · India | Available | [India regulated savings-bank deposit rate](https://links.sgx.com/FileOpen/IDBI%20Bank%20US%245b%20MTN%20Programme%20OC%20%2818%20Dec%2013%29.ashx?App=Prospectus&FileID=19979) | Unchanged regulated rate | 3.50% → 3.50% (through 2010-11-04) |
| 2008 · Global crisis in Brazil · Brazil | Available | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=BRA) | Annual | 11.66% → 8.51% (through 2017-09-11) |
| 2015 · Chinese bubble & long slump · China | Available (partial history) | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=CHN) | Annual | 1.50% → 1.50% (through 2025-01-01) |
| 2020 · COVID shock in Australia · Australia | Available | [RBA average online savings account rate ($10,000)](https://www.rba.gov.au/statistics/tables/xls/f04hist.xlsx) | Monthly (month-end) | 0.45% → 0.20% (through 2021-04-14) |
| 2020 · COVID shock · United States | Available | [FDIC national non-jumbo savings rate](https://fred.stlouisfed.org/series/SAVNRNJ) | Weekly | 0.09% → 0.06% (through 2020-08-18) |
| 2004 · Election uncertainty · India | Available | [India regulated savings-bank deposit rate](https://links.sgx.com/FileOpen/IDBI%20Bank%20US%245b%20MTN%20Programme%20OC%20%2818%20Dec%2013%29.ashx?App=Prospectus&FileID=19979) | Unchanged regulated rate | 3.50% → 3.50% (through 2004-11-08) |
| 2013 · Nikkei spring sell-off · Japan | Available | [World Bank / IMF deposit interest rate](https://data.worldbank.org/indicator/FR.INR.DPST?locations=JPN) | Annual | 0.54% → 0.54% (through 2013-11-28) |
| 2016 · Brexit vote shock · United Kingdom | Available | [Bank of England historical bank deposit rate](https://fred.stlouisfed.org/series/BDRUKM) | Monthly | 0.68% → 0.68% (through 2016-06-29) |
| 2018 · February volatility correction · United States | Available | [FDIC national non-jumbo savings rate](https://fred.stlouisfed.org/series/SAVNRNJ) | Weekly | 0.06% → 0.08% (through 2018-08-24) |
| 2018 · Fourth-quarter correction · United States | Available (partial history) | [FDIC national non-jumbo savings rate](https://fred.stlouisfed.org/series/SAVNRNJ) | Weekly | 0.08% → 0.09% (through 2018-12-24) |
| 2018 · Australian market correction · Australia | Available | [RBA average online savings account rate ($10,000)](https://www.rba.gov.au/statistics/tables/xls/f04hist.xlsx) | Monthly (month-end) | 0.95% → 0.90% (through 2019-04-24) |
| 2022 · Inflation & rate-hike bear market · United States | Unavailable | [FDIC national non-jumbo savings rate](https://fred.stlouisfed.org/series/SAVNRNJ) | Weekly | The verified weekly series does not cover the crash onset (2022-01-03). |
| 2024 · Election-result pullback · India | Unavailable | [India regulated savings-bank deposit rate](https://links.sgx.com/FileOpen/IDBI%20Bank%20US%245b%20MTN%20Programme%20OC%20%2818%20Dec%2013%29.ashx?App=Prospectus&FileID=19979) | Unchanged regulated rate | The verified unchanged regulated rate series does not cover the crash onset (2024-06-03). |

## Definitions and source URLs

- [World Bank / IMF deposit interest metadata](https://databank.worldbank.org/metadataglossary/world-development-indicators/series/FR.INR.DPST): commercial-bank demand, time or savings deposit rates. Products vary by country; these annual **deposit proxies are not a harmonized average of instant-access savings accounts**. Not central-bank policy rates.
- [FDIC savings series via FRED](https://fred.stlouisfed.org/series/SAVNRNJ): weekly national average APY on non-jumbo savings accounts, $2,500 tier, excluding credit unions. Begins May 2009; cannot supply the onset of 2007 or earlier US crashes.
- [Bank of England via FRED](https://fred.stlouisfed.org/series/BDRUKM): reconstructed monthly historical bank-deposit series. [Underlying BoE research datasets](https://www.bankofengland.co.uk/statistics/research-datasets). Product and source changes make this a deposit proxy.
- [RBA original online savings dataset](https://www.rba.gov.au/statistics/tables/xls/f04hist.xlsx), [RBA table notes](https://www.rba.gov.au/statistics/tables/notes.html#f4), [DBnomics retrieval mirror](https://db.nomics.world/RBA/F4/FRDIRSAO10K): indicative average online savings rates, not conditional bonus savings or the RBA policy cash rate.
- [IDBI issuer disclosure on SGX](https://links.sgx.com/FileOpen/IDBI%20Bank%20US%245b%20MTN%20Programme%20OC%20%2818%20Dec%2013%29.ashx?App=Prospectus&FileID=19979) and [SBI issuer disclosure](https://sbi.bank.in/webfiles/uploads/files/1391142552048_SBI_QIP_PLACEMENT_DOCUMENT.pdf): India's regulated savings rate was 3.5% during the whole selected 2008–2010 stock-market cycle. No assumed rate reduction is added merely because shares fell.

The machine-readable [savings-data.json](savings-data.json) retains original source URLs, retrieval URLs, source identities, product definitions, frequency, coverage, dates and source-response hashes for downloaded series. The rate-change table is separate from the [stock-index research](README.md). Regenerate with `node scripts/research-savings.mjs`; cached raw sources are in ignored `tmp/savings-research/`. Check provider/index redistribution terms before commercial publication.