COVID-19 short-term forecasts Confirmed 2021-09-01 Latin American Countries


General information

  • Forecasts produced by Jennie Castle, Jurgen Doornik, and David Hendry, researchers at the University of Oxford. These are our forecasts, and should not be considered official forecasts from, or endorsed by, any of: University of Oxford, Oxford Martin School, Nuffield College, or Magdalen College.
  • These forecasts are short term time-series extrapolations of the data. They are not based on epidemiological modelling or simulations. All forecasts are uncertain: their success can only be determined afterwards. Many mitigation strategies are in place, which, if successful, invalidate our forecasts. An explanation of our methods is provided below.
  • A list of notes is below. The most recent note:
    [2021-04-29]The `legacy' download for areas of England is stuck at April 26, so we switched to the newer downloads. The results now include Scotland, Wales, and Northern Ireland. The map, however, only shows England.

Peak increase in estimated trend of Confirmed in Latin America 2021-09-01

ArgentinaBahamasBarbadosBelizeBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaGuyanaHaitiHondurasJamaicaMexicoNicaraguaPanamaParaguayPeruSurinameTrinidad and TobagoUruguayVenezuela
Peak date (mm-dd)2021-05-272021-07-26 --2021-08-232021-06-012021-03-242021-06-042021-06-26 --2021-01-182021-07-292021-08-01 -- --2021-06-08 -- --2021-08-182021-08-192021-07-032021-06-022021-04-09 --2021-05-242021-04-092021-05-16
Peak daily increment 32513 172 84 2893 74845 7273 29826 1589 3111 425 179 18079 134 1075 2948 8725 529 5275 1698
Days since peak 97 37 9 92 161 89 67 226 34 31 85 14 13 60 91 145 100 145 108
Last total 5190948 18139 5072 16493 491340 20804215 1639123 4911082 466574 350468 501201 96067 475548 25770 20916 340559 68482 3369747 11735 458157 458614 2150006 29599 44957 385078 335233
Last daily increment 5328 0 40 140 461 27345 448 1996 2848 295 0 2007 5271 222 20 1802 351 17337 0 670 86 415 306 110 144 890
Last week 29022 422 331 600 2407 127654 3165 11997 13577 1553 1117 2007 20285 906 83 6669 4188 77986 568 3279 407 3837 1371 1207 620 5497
Previous peak date10-1910-172021-02-1712-032021-01-2208-0406-062021-01-162021-05-1707-2604-242021-04-1107-182021-06-2406-042021-02-032021-03-1510-0505-262021-01-07 --08-022021-06-0509-19 --09-08
Previous peak daily increment 14378 104 92 1122 2113 45269 7348 17013 2464 1405 7778 675 2590 196 177 1260 751 22832 177 3354 8379 261 119 1085
Low between peaks 5479 7 2 704 19228 1343 3454 400 -4305 125 5 2145 2 294 1490 4 276

Confirmed count forecast Latin America (bold red line in graphs) 2021-09-02 to 2021-09-08

DateArgentinaBahamasBarbadosBelizeBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaGuyanaHondurasJamaicaMexicoNicaraguaPanamaParaguayPeruSurinameTrinidad and TobagoUruguayVenezuela
2021-09-01 5190948 18139 5072 16493 491340 20804215 1639123 4911082 466574 350468 501201 96067 475548 25770 340559 68482 3369747 11735 458157 458614 2150006 29599 44957 385078 335233
2021-09-02 5202000 18420 5072 16580 492400 20847000 1639000 4917000 467600 350700 501900 96600 479800 25920 342600 69300 3400000 11780 459100 458900 2152000 29930 45160 385200 336300
2021-09-03 5209000 18600 5123 16580 492900 20882000 1640000 4922000 469400 351000 501900 96720 484100 26060 344400 69970 3423000 11780 459800 459000 2154000 30220 45400 385300 337100
2021-09-04 5214000 18600 5174 16610 493700 20909000 1640000 4925000 469400 351300 502500 96740 487600 26190 345700 70620 3441000 11780 460600 459200 2154000 30500 45650 385400 338000
2021-09-05 5217000 18600 5219 16670 494000 20922000 1641000 4928000 469400 351500 502700 96740 488600 26320 346700 71230 3447000 11780 461000 459200 2155000 30730 45790 385400 338900
2021-09-06 5222000 18900 5264 16720 494400 20935000 1641000 4931000 473500 351600 503100 96740 489200 26450 347500 71830 3455000 11780 461400 459300 2156000 30910 45900 385500 339700
2021-09-07 5227000 18920 5309 16790 494800 20958000 1641000 4933000 475800 351700 503300 96740 493500 26570 348300 72430 3466000 12260 461800 459400 2157000 31210 46110 385600 340600
2021-09-08 5233000 18920 5354 16870 495400 20986000 1641000 4935000 478300 352000 503400 97980 498400 26700 348900 73030 3484000 12260 462400 459500 2157000 31470 46250 385800 341500

Confirmed count average forecast Latin America (bold black line in graphs) 2021-09-02 to 2021-09-08

DateArgentinaBahamasBarbadosBelizeBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaGuyanaHondurasJamaicaMexicoNicaraguaPanamaParaguayPeruSurinameTrinidad and TobagoUruguayVenezuela
2021-09-01 5190948 18139 5072 16493 491340 20804215 1639123 4911082 466574 350468 501201 96067 475548 25770 340559 68482 3369747 11735 458157 458614 2150006 29599 44957 385078 335233
2021-09-02 5197000 18230 5106 16600 491600 20832000 1640000 4913000 469000 350700 501600 96360 480100 25910 341900 69010 3386000 11790 458600 458700 2151000 29860 45120 385200 335900
2021-09-03 5202000 18370 5130 16660 491800 20860000 1641000 4915000 470800 351000 501700 96590 483900 26020 342800 69510 3405000 11790 459000 458700 2152000 30050 45290 385200 336600
2021-09-04 5207000 18420 5157 16720 492200 20885000 1641000 4917000 471600 351300 501900 96770 487300 26120 343600 70070 3421000 11790 459400 458800 2152000 30250 45470 385300 337200
2021-09-05 5210000 18480 5183 16780 492400 20895000 1642000 4919000 472300 351500 502000 96900 489300 26230 344100 70610 3431000 11790 459700 458800 2153000 30420 45600 385400 337800
2021-09-06 5214000 18670 5210 16870 492700 20906000 1642000 4921000 475100 351700 502200 97050 491100 26340 345000 71170 3443000 11790 460000 458900 2154000 30580 45710 385400 338400
2021-09-07 5219000 18760 5238 16950 493100 20936000 1643000 4923000 476700 351900 502300 97190 494700 26450 345500 71650 3458000 12120 460400 459000 2154000 30780 45880 385500 339000
2021-09-08 5225000 18840 5266 17030 493600 20966000 1643000 4925000 478400 352200 502400 98010 498500 26560 346200 72030 3476000 12130 460900 459100 2155000 30980 46020 385600 339600

Further information

  • We believe these forecasts fill a useful gap in the short run. They give an indication of what is likely to happen in the next few days, removing some aspect of surprise. Moreover, a noticeable drop in comparison to the extrapolations could be an indication that the implemented policies are having some impact. It is difficult to understand exponential growth. We hope that these forecasts may help to convince viewers to adhere to the policies implemented by their respective governments, and keep all arguments factual and measured.
  • We use the data repository for the 2019 Novel Coronavirus Visual Dashboard operated by the Johns Hopkins University Center for Systems Science and Engineering. This is updated daily, but we tend to update our forecasts only every other day.
    US state data as of 2020-03-28 is courtesy of the New York Times.
  • We can only provide forecasts of what is measured. If confirmed cases are an underestimate of actual cases, then our forecasts will also be underestimates. No other epidemiological data is used. Data definition and collection differs between countries and may change over time.
  • We will update the methodology as we learn what is happening in the next few days or weeks. Once the number of cases levels off, there is no need to provide these forecasts anymore.
  • Countries where the counts are very low or stable have been omitted.
  • The graphs have dates on the horizontal axis (yyyy-mm-dd) and cumulative counts on the vertical axis. They show
    1. bold dark grey line (with circles): observed counts (Johns Hopkins CSSE);
    2. many light grey lines (with open circles): forecasts using different model settings and starting up to four periods back;
    3. red line (with open circles): single forecasts path using default model settings;
    4. black line (with crosses): average of all forecasts, recentered on the last observation;
    5. thin green lines: some indication of uncertainty around the red forecasts, but we do not know how reliable that is.
    Both the red line forecasts and the black lines are also given in the tables above. These forecasts differ, we are currently inclined to use the average forecasts.
  • The forecasts are constructed as follows:
    1. An overall `trend' is extracted by taking a window of the data at a time. In each window we draw `straight lines' which are selected using an automatic econometric procedure (`machine learning'). All straight lines are collected and averaged, giving the trend.
    2. Forecasts are made using the estimated trend, but we note that this must be done carefully, because simply extrapolating the flexible insample trend would lead to wildly fluctuating forecast. We use the `Cardt' method, which has been found to work well in other settings.
    3. Residuals from the trend are also forecast, and combined with trend forecasts into an overall forecast.
  • Scenario forecasts are constructed very differently: smooth versions of the Chinese experience are matched at different lag lengths with the path of each country. This probably works best from the peak, or the slowdown just before (but we include it for the UK nonetheless).
  • The forecast evaluation shows past forecasts, together with the outcomes (in the grey line with circles).
  • EU-BS is Estonia, Latvia, and Lithuania together.
  • This paper describes the methodology and gives further references. Also available as Nuffield Economics Discussion Paper 2020-W06. Still preliminary is the documentation of the medium term forecasts.

Recent changes and notes

[2021-04-29]The `legacy' download for areas of England is stuck at April 26, so we switched to the newer downloads. The results now include Scotland, Wales, and Northern Ireland. The map, however, only shows England.
[2021-01-07]Slideshow of forecasts, errors, and actuals 2020-06-30 to 2021-01-02: how England lost the battle.
[2020-10-27]Statistical short-term forecasting of the COVID-19 Pandemic (Jurgen Doornik, Jennie Castle, and David Hendry) is now published at the Journal of Clinical Immunology and Immunotherapy. open access
[2020-10-11]Short-term forecasting of the coronavirus pandemic (Jurgen Doornik, Jennie Castle, and David Hendry) is now in press at the International Journal of Forecasting. open access
[2020-10-10]Removed forecasts from the Chinese scenarios, while investigating possibility to use own history from the first wave.
Added information on the previous peak (if present) to the peak tables.
Local forecasts for England: now dropping last four observations.
[2020-07-01] Modified the short-term model to allow for (slowly changing) seasonality. Many countries show clear seasonality after the initial period, likely caused by institutional factors regarding data collection. This seasonality was also getting in the way of peak detection. As a consequence estimates of the peak date may have changed for countries with strong seasonality.
Added forecasts of cumulative confirmed cases for lower tier local authorities of England. The data is available from 2020-07-02 including all tests (pillar one and two). Only authorities with more than 5 cases in the previous week are included.
[2020-06-29] Tables in April included the world, but not the world as we know it (double counting China and the US). So removed the world from those old tables.
Why short-term forecasts can be better than models for predicting how pandemics evolve just appeared at The Conversation.
Thursday 2 July webinar at the FGV EESP - São Paolo School of Economics. This starts at 16:00 UK time (UTC+01:00) and streamed here.
[2020-06-24] Research presentation on short-term COVID-19 forecasting on 26 June (14:00 UK time) at the Quarterly Forecasting Forum of the IIF UK Chapter.
[2020-06-06] Removed Brazil from yesterday's forecasts (only; last observation 2020-06-05).
[2020-06-04] Data issues with confirmed cases for France.
Added an appendix to the short term paper with further forecast comparisons for European and Latin American countries.
Both Sweden and Iran have lost their peak in confirmed cases. For Sweden the previous peak was on 24 April (daily peak of 656 cases), for Iran it was on 31 March (peak of 3116). For Iran this looks like a second wave, with increasing daily counts for the last four weeks. For Sweden this is a sudden jump in confirmed cases in the last two days, compared to a fairly steady weekly pattern over the previous six weeks.
[2020-05-20] Problem with UK confirmed cases: negative daily count. This makes the forecasts temporarily unreliable.
Updated the second paper.
[2020-05-18] Minor fixes to the improved version of scenario forecasting, backported to 2020-05-13.
[2020-05-13] We now omit countries with fewer than 200 confirmed cases in the last week (25 for deaths).
The short-term paper has some small updates, including further comparisons with other models.
Data for Ecuador are not reliable enough for forecasting.
Switched to an improved version of scenario forecasting.
[2020-05-06] The New York Times is in the process of redefining its US state data. Unfortunately, at the moment only the last observation has changed (e.g New York deaths jumped from 19645 on 2020-05-05 to 25956 a day later). This means the data is currently useless; however it does bring it close to the Johns Hopkins/CSSE count (25626 on 2020-05-06). The aggregate US count is based on JH/CSSE so unaffected. We now use Johns Hopkins/CSSE US state data, including all states with sufficient counts. So the new forecasts cannot be compared to those previously.
A minor change is that we show the graph without scenario forecast if no peak has been detected yet.
[2020-04-29] See our blog entry at the International Institute of Forecasters.
US history of death counts revised in Johns Hopkins/CSSE data.
UK death counts have been revised to include the deaths in care homes. In the Johns Hopkins/CSSE data set, which we use, the entire history has been revised. So forecasts made up to 2020-04-29 cannot be compared to later outcomes. In the ECDC data set only the last observation has changed, causing a jump in the series.
[2020-04-27] Our short-term COVID-19 forecasting paper is now available as Nuffield Economics Discussion Paper 2020-W06.
A small adjustment has been made to the scenario forecast methodology, and will be documented shortly.
[2020-04-24] A summary of our work on short-term COVID-19 forecasting appeared as a voxeu.
[2020-04-17] Bird and Nielsen look into nowcasting death counts in England.
[2020-04-16] Added scenario forecasts to all graphs now. This would now be the preferred forecast for most.
This is the first time with a peak in confirmed UK cases (also for deaths, but this is uncertain because it is at the same date).
[2020-04-10] Updated documentation with better description of short-term estimates and peak determination.
[2020-04-09] Added table with estimated peak dates (if happened) and dates to and since the peak. Note that this can be a local peak, and subsequent re-acceleration (or data revisions) can result in a new peak later.
[2020-04-08] Minor correction to peak estimates. Added table with scenario forecasts.
[2020-04-06] Added a post hoc estimate of the peak number of cases. This needs at least three confirmed observations (four for deaths) after the event. It is based on the averaged smooth trend, and can change later or be a local peak. It is marked with a vertical line with the date label, or a date with left arrow in the bottom left corner of the graph. This is backported to 2020-04-04.
[2020-04-02] Now including more US States, based on New York Times data.
[2020-03-31] Scenario forecasts, based on what happened in China earlier this year, are presented for several countries (line marked with x). Created more plausible 90% confidence bands (dotted line in same colour).
[2020-03-26] Scenario forecasts that are based on what happened in China earlier this year, only for Italy.
[2020-03-24] Our forecasts are starting to overestimate in some cases. This was always expected to happen when the increase starts to slow down. Scenario forecasts that are based on what happened in China earlier this year, but only for Italy and Spain sofar.

Initial visual evaluation of forecasts of Confirmed