COVID-19 short-term forecasts Deaths 2020-08-12 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:
    [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.

Peak increase in estimated trend of Deaths in Latin America 2020-08-12

ArgentinaBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaHondurasMexicoPanamaPeruVenezuela
Peak date --08-0107-1507-1708-0608-08 --05-10 --06-0507-29 --07-2307-23 --
Peak daily increment 79 1064 815 321 10 170 43 32 27 3176
Days from 100 to peak 85 109 93 116 13 39 5 82 98 107
Days from peak/2 to peak 100 100 62 110 110 40 29 114 117 77
Last total 5213 3827 104201 10205 13837 263 1371 5984 577 2267 1533 54666 1703 21501 247
Last daily increment 209 66 1175 27 362 8 25 33 7 34 18 737 23 0 9
Last week 962 362 5708 316 1898 63 125 107 64 148 87 4149 129 1077 45
Days since peak 11 28 26 6 4 94 68 14 20 20

Deaths count forecast Latin America (bold red line in graphs) 2020-08-13 to 2020-08-19

DateArgentinaBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaHondurasMexicoPanamaPeruVenezuela
2020-08-12 5213 3827 104201 10205 13837 263 1371 5984 577 2267 1533 54666 1703 21501 247
2020-08-13 5399 3897 105400 10360 14150 272 1393 6010 587 2331 1554 55100 1726 21660 254
2020-08-14 5587 3966 106500 10450 14450 281 1416 6035 597 2375 1576 55860 1749 21810 261
2020-08-15 5781 4035 107400 10520 14750 290 1440 6059 606 2398 1596 56580 1771 21810 268
2020-08-16 5977 4104 107900 10590 15050 299 1464 6083 616 2418 1618 56870 1794 22260 275
2020-08-17 6180 4174 108500 10670 15350 309 1489 6107 626 2428 1640 57400 1816 22450 283
2020-08-18 6391 4244 109600 10720 15650 318 1514 6131 636 2438 1662 58280 1839 22620 290
2020-08-19 6608 4315 110900 10760 15960 327 1540 6155 646 2477 1683 58990 1862 22660 298

Deaths count average forecast Latin America (bold black line in graphs) 2020-08-13 to 2020-08-19

DateArgentinaBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaHondurasMexicoPanamaPeruVenezuela
2020-08-12 5213 3827 104201 10205 13837 263 1371 5984 577 2267 1533 54666 1703 21501 247
2020-08-13 5306 3891 105200 10270 14130 271 1393 6004 587 2300 1547 55060 1721 21650 251
2020-08-14 5461 3963 106200 10360 14440 280 1417 6028 598 2339 1567 55810 1742 21820 259
2020-08-15 5626 4036 107100 10450 14740 290 1444 6052 609 2369 1588 56520 1763 21930 266
2020-08-16 5793 4108 107700 10540 15060 300 1470 6071 621 2396 1610 56790 1785 22210 274
2020-08-17 5984 4185 108400 10640 15400 310 1493 6092 633 2422 1632 57250 1808 22420 281
2020-08-18 6187 4272 109500 10710 15750 321 1520 6119 646 2452 1654 58130 1831 22610 289
2020-08-19 6389 4351 110700 10790 16100 332 1546 6148 658 2493 1678 58780 1855 22800 298

Deaths count scenario forecast (bold purple line in graphs) 2020-08-13 to 2020-08-21

DateArgentinaBoliviaBrazilChileColombiaCosta RicaDominican RepublicEcuadorEl SalvadorGuatemalaHondurasMexicoPanamaPeruVenezuela
2020-08-12 5213 3827 104201 10205 13837 263 1371 5984 577 2267 1533 54666 1703 21501 247
2020-08-13 5376 3905 105000 10290 14120 272 1386 6005 589 2289 1551 55200 1721 21640 253
2020-08-14 5543 3961 105800 10350 14410 281 1405 6025 601 2311 1565 55860 1741 21760 261
2020-08-15 5722 4013 106600 10400 14700 290 1422 6045 612 2330 1579 56460 1758 21880 269
2020-08-16 5910 4067 107400 10440 15000 299 1445 6063 626 2348 1595 57140 1774 21990 278
2020-08-17 6085 4126 108100 10480 15330 309 1465 6081 640 2367 1608 57850 1789 22090 286
2020-08-18 6285 4175 108800 10520 15630 319 1487 6097 654 2382 1624 58660 1804 22190 294
2020-08-19 6501 4227 109400 10550 15960 328 1512 6114 667 2393 1637 59450 1816 22280 303
2020-08-20 6705 4279 110000 10610 16310 337 1536 6130 679 2407 1648 60190 1828 22350 310
2020-08-21 6916 4319 110600 10650 16670 344 1558 6144 691 2420 1657 60920 1838 22430 318

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

[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 Deaths