COVID-19 short-term forecasts Confirmed 2021-09-23 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 2021-09-23

ArgentinaBahamasBarbadosBelizeBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaGuyanaHaitiHondurasJamaicaMexicoNicaraguaPanamaParaguayPeruSurinameTrinidad and TobagoUruguayVenezuela
Peak date (mm-dd)2021-05-272021-07-26 --2021-09-012021-06-012021-09-182021-06-042021-06-26 --2021-01-182021-07-292021-04-112021-08-24 --2021-06-082021-08-132021-08-232021-08-11 --2021-07-032021-06-022021-04-10 --2021-05-242021-04-092021-05-16
Peak daily increment 32516 172 106 2893 95712 7273 29826 1589 3070 674 3895 179 1515 767 18312 1075 2953 8699 529 5270 1699
Days since peak 119 59 22 114 5 111 89 248 56 165 30 107 41 31 43 82 113 166 122 167 130
Last total 5246998 20288 7065 19429 498331 21308178 1649409 4946811 518632 356321 507020 102024 542024 30444 21453 361527 81394 3608976 13730 465471 459751 2170475 39140 49442 388191 358462
Last daily increment 1733 0 161 244 347 24611 859 1608 2701 279 0 0 4037 258 22 0 435 11808 0 324 31 1048 371 331 123 0
Last week 9839 258 707 897 1631 227959 3006 9215 13469 1605 1160 2323 16863 1372 123 4820 2804 55993 705 1688 227 6095 2712 1299 742 5061
Previous peak date10-1910-172021-02-1812-032021-01-222021-03-2406-062021-01-162021-05-1707-2604-2408-0507-182021-06-2406-042021-02-032021-03-1810-05 --2021-01-07 --08-022021-06-0509-19 --09-08
Previous peak daily increment 14376 104 92 1113 2113 74829 7360 17013 2571 1408 7756 420 2699 195 177 1356 660 23278 3350 8364 261 119 1086
Low between peaks 5479 7 2 704 16999 1343 3453 400 -4346 71 424 5 553 42 2152 294 1487 4 276

Confirmed count forecast Latin America (bold red line in graphs) 2021-09-24 to 2021-09-30

DateArgentinaBahamasBarbadosBelizeBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaGuyanaHondurasJamaicaMexicoNicaraguaPanamaParaguayPeruSurinameTrinidad and TobagoUruguayVenezuela
2021-09-23 5246998 20288 7065 19429 498331 21308178 1649409 4946811 518632 356321 507020 102024 542024 30444 361527 81394 3608976 13730 465471 459751 2170475 39140 49442 388191 358462
2021-09-24 5252000 20610 7141 19480 498800 21317000 1650000 4949000 522700 356500 507500 102200 546000 30710 363500 81910 3619000 13730 465900 459800 2171000 39600 49560 388400 359700
2021-09-25 5255000 20650 7229 19480 499200 21356000 1650000 4951000 523100 356800 507800 102200 549500 30940 364500 82870 3631000 13730 466300 459900 2172000 39720 49760 388500 360700
2021-09-26 5256000 20650 7326 19480 499400 21366000 1651000 4953000 523100 356900 508900 102200 550300 31160 364500 83600 3645000 13730 466600 460000 2173000 39990 49880 388600 361700
2021-09-27 5259000 20820 7423 19690 499500 21366000 1651000 4954000 526300 357100 509000 104000 551000 31360 366800 84220 3650000 13730 466700 460000 2174000 40330 49900 388700 362600
2021-09-28 5261000 20880 7521 19720 499900 21366000 1651000 4956000 529000 357400 509200 104000 554800 31570 367300 84820 3663000 14350 467100 460000 2174000 40690 50130 388800 363600
2021-09-29 5263000 20920 7622 19950 500200 21393000 1651000 4958000 530600 357700 509300 104000 558900 31770 368300 85360 3674000 14350 467400 460100 2175000 41100 50390 389000 364500
2021-09-30 5266000 20950 7724 20150 500500 21420000 1652000 4959000 532100 357900 509500 104200 561900 31970 368300 85880 3684000 14350 467800 460100 2176000 41520 50670 389100 365500

Confirmed count average forecast Latin America (bold black line in graphs) 2021-09-24 to 2021-09-30

DateArgentinaBahamasBarbadosBelizeBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaGuyanaHondurasJamaicaMexicoNicaraguaPanamaParaguayPeruSurinameTrinidad and TobagoUruguayVenezuela
2021-09-23 5246998 20288 7065 19429 498331 21308178 1649409 4946811 518632 356321 507020 102024 542024 30444 361527 81394 3608976 13730 465471 459751 2170475 39140 49442 388191 358462
2021-09-24 5249000 20420 7185 19590 498700 21322000 1650000 4948000 521200 356600 507000 102100 545500 30690 362500 81870 3616000 13720 465700 459800 2171000 39580 49670 388300 359300
2021-09-25 5250000 20460 7269 19660 498900 21387000 1651000 4950000 522800 356900 507100 102200 548000 30890 363200 82440 3623000 13730 465900 459800 2172000 39980 49860 388400 360100
2021-09-26 5251000 20490 7366 19720 499000 21396000 1651000 4951000 524200 357100 507700 102400 549200 31080 363500 82960 3634000 13740 466000 459800 2173000 40400 50000 388400 360800
2021-09-27 5253000 20630 7457 19930 499100 21402000 1651000 4952000 526100 357300 507700 103400 550400 31270 364900 83480 3639000 13760 466100 459900 2173000 40830 50080 388500 361500
2021-09-28 5255000 20690 7548 20010 499300 21409000 1652000 4954000 527800 357500 507800 103500 553300 31450 365400 83930 3650000 14340 466300 459900 2174000 41280 50270 388600 362200
2021-09-29 5257000 20770 7645 20180 499500 21425000 1652000 4955000 529400 357800 507900 103700 556000 31640 366200 84320 3660000 14360 466600 459900 2175000 41730 50470 388700 362800
2021-09-30 5259000 20840 7738 20330 499700 21445000 1653000 4957000 530900 358000 508100 104000 558100 31820 366600 84730 3669000 14360 466800 460000 2175000 42180 50660 388800 363500

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