Corona's Exponential Curve Slope Tracking, March 20 snbchf.com

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George Dorgan
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NEXT UPDATE on March24, with March 23 data.

The Essence: Slop of the Curve

Total World: Doubling of active cases every 3 days.
Tendency Rising.

U.S., Spain, Germany, U.K., Switzerland
Double in less than 2 days:

France: Double in 3 days.

Italy: Reduced slope to doubling in 4 or 5 days.

China, South Korea: Curve is flat.
Iran: Worst slope increase is over at least according to official figures.

Curve Trends Corona March 20 Slope Derivation

Exponential Growth and Corona

The more mathematically versed folks under us have understood that it the slope (or steepness / derivation) of the Corona expansion curve is important.

The following statistics is based on the Worldometer data, that rather shows the “first dimension”; we however, focus on the “second dimension”, the slope of the curve.
This is far more useful, because for such exponential curve, the slope is key.The video explains the details.

Exponential Growth

It took the Corona Virus 20 days to grow from 100 to 1000
and 13 days to grow to 1000 to 10000.

Attention here: The Y axis has a logarithmic scale.

Formulae Exponential Curve

ΔN_d is the number of new cases per day.

Basic Reproduction Number

E is the number of people one person typically infects, the so-called basic reproduction number.
In Wikipedia it is called R₀
According to some initial research cited in Wikipedia (e.g. here or here), this number is between 1.4 and 3.9 for Covid19. This would be inferior to the one of SARS, the 2003 outbreak, which had values between 2 and 5.

However this value is highly unprobable, given that SARS only affected 8000 people. Moreover, the high variance of the values are worrying: Minimum 1.4 and maximum 3.9.

Probability for infection

p is the probability that this infection happens from one person to another.

Key for policy makers is to contain the number of new transmission E*p.
This is mostly done using measures like

school-closing, social distancing, hand disinfection and lock-downs.

Inflection point from exponential to logistic curve

The second derivation of the formula leads to the inflection point, where the curve converts to a logistic curve.

Reasons are :

E*p gets reduced thanks to the measures above,
for example from 1.15 to 1.05
Most people cannot be infected anymore because they have had the disease already, the so-called herd immunity. According to the German Robert Koch Institute this can take up to 2 years.

Explanations for the table below

We track average (ΔN_d/ N_d) over 3 days.

ΔN_dare new cases.

N_d corresponds to the active cases, the ones that may transmit the virus.

When ΔN_d/ N_dis bigger than the previous days, this means that the slope of the curve increases, hence implicitly the growth factor ΔN_d/ N_d-1

Key Points as of March 20

Massive rise in slope in the United State, Germany and Switzerland
But also in Brazil, Pakistan and Turkey.

Country	Total Cases	Latest Period ΔN_d/ N_dAverage New Cases in% of Active Cases per Day		Previous Periods ΔN_d/ N_dAverage New Cases in % of Active Cases per Day				Curve Trend	Curve Slope Tendency
Country	Total Cases	New Cases last 3 days	March 18-20 ΔN_d/ N_d	March 15-17	March 12-14	March 08-11	March 04-07	Curve Trend	Curve Slope Tendency
Total World	275,557	77379	34%	18%	19%	11%	8%	Double in 2-3 days	Rising vs (nearly) all periods
China	80,967	86	0.24%	0.16%	0.07%	0.16%	0.42%	Flat or Flattening	Flat or Near Flat
Italy	47,021	15,515	29%	19%	27%	32%	37%	Double in 4 to 5 days	Slope Mostly Rising
Spain	21,571	9,745	57%	32%	67%	96%	52%	Double in less than 2 days	Slope Rising Again After Slowing
Germany	19,848	10,481	77%	35%	48%	35%	84%	Double in less than 2 days	Rising vs nearly all periods
Iran	19,644	3,475	15%	15%	22%	20%	48%	Double in 5 to 10 days	Only Recently Rising
USA	19,383	12,944	158%	44%	41%	54%	79%	Double in less than 2 days	Rising vs nearly all periods
France	12,612	4,882	37%	25%	33%	36%	94%	Double in 2-3 days	Rising vs nearly all periods
S. Korea	8,652	332	2%	1%	1%	3%	92%	Flat or Flattening	Flat or Near Flat
Switzerland	5,615	2,873	71%	34%	37%	36%	94%	Double in less than 2 days	Rising vs nearly all periods
UK	3,983	2,033	62%	25%	53%	76%	92%	Double in less than 2 days	Slope Mostly Rising
Netherlands	2,994	1,289	45%	26%	31%	42%	179%	Double in 2-3 days	Rising vs nearly all periods
Austria	2,649	1,317	68%	35%	56%	52%	59%	Double in less than 2 days	Rising vs nearly all periods
Belgium	2,257	1,014	49%	27%	40%	22%	325%	Double in 2-3 days	Rising vs nearly all periods
Norway	1,959	489	15%	11%	25%	76%	93%	Double in 5 to 10 days	Slope Rising Again After Slowing
Sweden	1,639	443	15%	8%	31%	53%	113%	Double in 5 to 10 days	Slope Rising Again After Slowing
Denmark	1,255	278	11%	6%	20%	468%	43%	Double in 5 to 10 days	Only Recently Rising
Canada	1,087	489	69%	50%	46%	24%	33%	Double in less than 2 days	Rising vs all periods
Malaysia	1,030	357	59%	71%	24%	20%	102%	Double in less than 2 days	Slope Falling or Constant
Portugal	1,020	572	114%	56%	62%	45%	106%	Double in less than 2 days	Rising vs nearly all periods
Japan	1,007	129	7%	4%	11%	12%	17%	Double in 10 – 15 days	Only Recently Rising
Brazil	970	624	139%	43%	63%	43%	213%	Double in less than 2 days	Rising vs nearly all periods
Australia	928	476	73%	31%	40%	26%	39%	Double in less than 2 days	Rising vs nearly all periods
Czechia	833	399	70%	43%	34%	65%	105%	Double in less than 2 days	Rising vs nearly all periods
Diamond Princess	712	16	2%	0%	0%	0%	0%	Flat or Flattening	Rising vs nearly all periods
Israel	705	368	65%	25%	34%	82%	30%	Double in less than 2 days	Slope Mostly Rising
Ireland	683	391	103%	43%	68%	32%	213%	Double in less than 2 days	Rising vs nearly all periods
Turkey	670	572	3178%	511%	167%	New	New	Double in less than 2 days	Slope Mostly Rising
Pakistan	501	254	292%	248%	24%	65%	5%	Double in less than 2 days	Rising vs (nearly) all periods
Greece	495	108	17%	24%	43%	13%	211%	Double in 5 to 10 days	Slope Falling or Constant
Luxembourg	484	344	229%	59%	210%	33%	50%	Double in less than 2 days	Rising vs (nearly) all periods
Qatar	470	28	3%	11%	10%	521%	13%	Flat or Flattening	Slope Falling or Constant
Finland	450	128	20%	15%	95%	56%	50%	Double in 5 to 10 days	Only Recently Rising
Chile	434	233	127%	77%	55%	90%	100%	Double in less than 2 days	Rising vs (nearly) all periods
Ecuador	426	315	389%	102%	22%	5%	25%	Double in less than 2 days	Rising vs (nearly) all periods
Poland	425	187	72%	52%	77%	104%	New	Double in less than 2 days	Only Recently Rising
Iceland	409	162	34%	18%	30%	18%	98%	Double in 2-3 days	Rising vs (nearly) all periods
Singapore	385	119	37%	17%	14%	21%	22%	Double in 2-3 days	Rising vs (nearly) all periods
Indonesia	369	197	79%	31%	67%	188%	25%	Double in less than 2 days	Slope Mostly Rising
Saudi Arabia	344	173	57%	22%	44%	158%	150%	Double in less than 2 days	Slope Mostly Rising
Slovenia	341	66	12%	17%	73%	94%	New	Double in 5 to 10 days	Slope Falling or Constant
Thailand	322	145	105%	69%	32%	13%	15%	Double in less than 2 days	Rising vs (nearly) all periods
Romania	308	91	27%	27%	62%	85%	75%	Double in 4 to 5 days	Slope Falling or Constant
Bahrain	298	57	13%	6%	4%	35%	18%	Double in 5 to 10 days	Slope Mostly Rising
Egypt	285	89	37%	36%	51%	6%	1150%	Double in 2-3 days	Slope Falling or Constant
Estonia	283	58	17%	32%	206%	15%	100%	Double in 5 to 10 days	Slope Falling or Constant
Peru	263	146	128%	69%	64%	29%	2%	Double in less than 2 days	Rising vs (nearly) all periods
Hong Kong	256	88	51%	15%	8%	8%	3%	Double in less than 2 days	Rising vs (nearly) all periods
Russia	253	139	91%	36%	76%	10%	300%	Double in less than 2 days	Rising vs (nearly) all periods
India	249	106	42%	18%	20%	23%	233%	Double in 2-3 days	Rising vs (nearly) all periods
Philippines	230	43	14%	25%	46%	358%	New	Double in 5 to 10 days	Slope Falling or Constant
Iraq	208	54	24%	20%	27%	9%	17%	Double in 4 to 5 days	Slope Falling or Constant
South Africa	202	117	103%	41%	64%	138%	New	Double in less than 2 days	Slope Mostly Rising
Panama	200	131	125%	31%	133%	New	New	Double in less than 2 days	Only Recently Rising
Lebanon	177	53	20%	12%	18%	31%	29%	Double in 5 to 10 days	Slope Mostly Rising
Mexico	164	82	124%	85%	150%	10%	0%	Double in less than 2 days	Slope Falling or Constant
Kuwait	159	29	10%	9%	15%	5%	2%	Double in 10 – 15 days	Slope Falling or Constant
Argentina	158	79	61%	26%	48%	31%	200%	Double in less than 2 days	Rising vs (nearly) all periods
San Marino	151	32	12%	7%	22%	44%	36%	Double in 5 to 10 days	Only Recently Rising
Colombia	145	80	121%	65%	48%	200%	New	Double in less than 2 days	Slope Mostly Rising
UAE	140	27	14%	14%	6%	19%	New	Double in 5 to 10 days	Slope Falling or Constant
Slovakia	137	40	30%	40%	113%	58%	New	Double in 2-3 days	Slope Falling or Constant
Armenia	136	58	107%	111%	567%	0%	0%	Double in less than 2 days	Slope Falling or Constant
Serbia	135	63	46%	19%	94%	275%	New	Double in 2-3 days	Only Recently Rising
Taiwan	135	58	60%	25%	6%	3%	3%	Double in less than 2 days	Rising vs (nearly) all periods
Croatia	130	61	55%	27%	35%	15%	8%	Double in less than 2 days	Rising vs (nearly) all periods
Bulgaria	127	46	39%	34%	189%	63%	New	Double in 2-3 days	Only Recently Rising
Costa Rica	113	63	78%	46%	36%	300%	New	Double in less than 2 days	Slope Mostly Rising
Latvia	111	51	68%	45%	59%	New	0%	Double in less than 2 days	Slope Mostly Rising
Uruguay	110	81	675%	208%	New	New	New	Double in less than 2 days	Only Recently Rising
Algeria	94	33	46%	33%	28%	1%	34%	Double in 2-3 days	Rising vs (nearly) all periods
Vietnam	91	25	23%	12%	23%	113%	New	Double in 4 to 5 days	Only Recently Rising
Bosnia	89	55	87%	21%	67%	33%	New	Double in less than 2 days	Rising vs (nearly) all periods
Morocco	86	42	88%	54%	80%	50%	25%	Double in less than 2 days	Rising vs (nearly) all periods
Hungary	85	35	40%	23%	44%	40%	New	Double in 2-3 days	Slope Falling or Constant
Jordan	85	37	New	New	0%	0%	25%	Double in less than 2 days	Slope Falling or Constant
Faeroe Islands	80	33	122%	141%	117%	0%	New	Double in less than 2 days	Slope Falling or Constant
Brunei	78	22	18%	13%	88%	New	New	Double in 5 to 10 days	Only Recently Rising
North Macedonia	76	45	125%	50%	29%	33%	50%	Double in less than 2 days	Rising vs (nearly) all periods
Andorra	75	36	1200%	1267%	0%	0%	0%	Double in less than 2 days	Slope Falling or Constant
Cyprus	75	26	33%	29%	111%	New	New	Double in 2-3 days	Only Recently Rising
Sri Lanka	73	29	107%	126%	267%	New	New	Double in less than 2 days	Slope Falling or Constant
Dominican Republic	72	51	155%	30%	40%	38%	25%	Double in less than 2 days	Rising vs (nearly) all periods
Albania	70	15	14%	15%	55%	New	New	Double in 5 to 10 days	Slope Falling or Constant
Belarus	69	33	46%	13%	100%	13%	125%	Double in 2-3 days	Slope Falling or Constant
Lithuania	69	43	179%	71%	67%	50%	0%	Double in less than 2 days	Rising vs (nearly) all periods
Moldova	66	36	100%	50%	100%	50%	New	Double in less than 2 days	Slope Falling or Constant
Venezuela	65	32	533%	517%	New	New	New	Double in less than 2 days	Only Recently Rising
Malta	64	26	51%	39%	67%	25%	New	Double in less than 2 days	Slope Falling or Constant
Tunisia	54	29	54%	13%	52%	150%	0%	Double in less than 2 days	Slope Mostly Rising
Kazakhstan	52	19	106%	150%	New	New	New	Double in less than 2 days	Slope Falling or Constant
New Zealand	52	40	190%	24%	13%	0%	100%	Double in less than 2 days	Rising vs (nearly) all periods
Cambodia	51	18	100%	144%	67%	25%	New	Double in less than 2 days	Slope Falling or Constant
Guadeloupe	51	45	500%	33%	New	New	New	Double in less than 2 days	Only Recently Rising
Oman	48	15	50%	47%	4%	4%	10%	Double in 2-3 days	Rising vs (nearly) all periods
Palestine	48	7	6%	3%	9%	14%	New	Double in 10 – 15 days	Only Recently Rising
Senegal	47	20	35%	11%	189%	0%	25%	Double in 2-3 days	Slope Falling or Constant
Azerbaijan	44	10	30%	58%	17%	6%	50%	Double in 2-3 days	Slope Falling or Constant
Georgia	44	10	11%	4%	8%	21%	83%	Double in 5 to 10 days	Slope Mostly Rising
Ukraine	41	27	450%	183%	67%	0%	0%	Double in less than 2 days	Rising vs (nearly) all periods
Burkina Faso	40	25	417%	217%	0%	New	New	Double in less than 2 days	Slope Mostly Rising
R茅union	38	29	161%	17%	167%	New	New	Double in less than 2 days	Only Recently Rising
Uzbekistan	33	22	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Martinique	32	17	57%	17%	78%	New	New	Double in less than 2 days	Only Recently Rising
Liechtenstein	28	9	75%	125%	100%	0%	0%	Double in less than 2 days	Slope Falling or Constant
Cameroon	27	17	283%	133%	0%	0%	New	Double in less than 2 days	Rising vs (nearly) all periods
Afghanistan	24	2	6%	33%	19%	19%	New	Double in 10 – 15 days	Slope Falling or Constant
Honduras	24	16	178%	56%	17%	New	New	Double in less than 2 days	Slope Mostly Rising
Cuba	21	16	133%	8%	New	New	New	Double in less than 2 days	Only Recently Rising
Bangladesh	20	10	111%	56%	22%	New	New	Double in less than 2 days	Slope Mostly Rising
Jamaica	19	7	29%	17%	100%	New	New	Double in 4 to 5 days	Only Recently Rising
DRC	18	15	250%	17%	33%	New	New	Double in less than 2 days	Slope Mostly Rising
Paraguay	18	9	43%	10%	13%	100%	New	Double in 2-3 days	Slope Mostly Rising
Macao	17	4	New	New	New	New	0%	Double in less than 2 days	Slope Falling or Constant
Rwanda	17	10	333%	200%	New	New	New	Double in less than 2 days	Only Recently Rising
Bolivia	16	4	13%	7%	133%	New	New	Double in 5 to 10 days	Only Recently Rising
Ghana	16	9	150%	83%	New	New	New	Double in less than 2 days	Only Recently Rising
French Guiana	15	4	19%	19%	13%	New	New	Double in 5 to 10 days	Slope Falling or Constant
Guyana	15	8	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Guam	14	9	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Montenegro	14	12	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Puerto Rico	14	9	100%	22%	New	New	New	Double in less than 2 days	Only Recently Rising
Maldives	13	0	0%	10%	8%	75%	New	Flat or Flattening	Flat or Near Flat
Channel Islands	12	6	67%	33%	17%	New	New	Double in less than 2 days	Slope Mostly Rising
Guatemala	12	4	133%	233%	New	New	New	Double in less than 2 days	Slope Falling or Constant
Mauritius	12	12	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Nigeria	12	9	150%	17%	0%	25%	0%	Double in less than 2 days	Rising vs (nearly) all periods
French Polynesia	11	8	89%	0%	New	New	New	Double in less than 2 days	Only Recently Rising
Monaco	11	2	33%	117%	33%	0%	0%	Double in 2-3 days	Slope Falling or Constant
Gibraltar	10	7	New	New	New	0%	New	Double in less than 2 days	Slope Falling or Constant
Ethiopia	9	3	100%	167%	New	New	New	Double in less than 2 days	Slope Falling or Constant
Ivory Coast	9	5	167%	100%	0%	New	New	Double in less than 2 days	Slope Mostly Rising
Togo	9	8	267%	0%	0%	0%	New	Double in less than 2 days	Rising vs (nearly) all periods
Trinidad and Tobago	9	4	67%	50%	New	New	New	Double in less than 2 days	Only Recently Rising
Kenya	7	3	100%	133%	New	New	New	Double in less than 2 days	Slope Falling or Constant
Mayotte	7	4	133%	67%	New	New	New	Double in less than 2 days	Only Recently Rising
Seychelles	7	3	50%	33%	New	New	New	Double in 2-3 days	Only Recently Rising
Barbados	6	4	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Equatorial Guinea	6	5	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Kyrgyzstan	6	6	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Mongolia	6	1	33%	133%	0%	New	New	Double in 2-3 days	Slope Falling or Constant
Tanzania	6	5	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Aruba	5	2	33%	17%	New	New	New	Double in 2-3 days	Only Recently Rising
Bahamas	4	3	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Gabon	4	3	100%	0%	New	New	New	Double in less than 2 days	Only Recently Rising
Saint Martin	4	2	33%	0%	0%	New	New	Double in 2-3 days	Slope Mostly Rising
Suriname	4	3	100%	0%	New	New	New	Double in less than 2 days	Only Recently Rising
CAR	3	2	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Cayman Islands	3	2	67%	0%	New	New	New	Double in less than 2 days	Only Recently Rising
Congo	3	2	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Curacao	3	3	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Madagascar	3	3	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Namibia	3	1	17%	0%	New	New	New	Double in 5 to 10 days	Only Recently Rising
St. Barth	3	0	0%	67%	0%	New	New	Flat or Flattening	Flat or Near Flat
U.S. Virgin Islands	3	1	33%	33%	New	New	New	Double in 2-3 days	Slope Falling or Constant
Benin	2	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Bermuda	2	2	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Bhutan	2	1	33%	0%	0%	0%	New	Double in 2-3 days	Rising vs (nearly) all periods
Greenland	2	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Guinea	2	1	33%	0%	New	New	New	Double in 2-3 days	Only Recently Rising
Haiti	2	2	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Isle of Man	2	2	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Liberia	2	0	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Mauritania	2	1	33%	0%	New	New	New	Double in 2-3 days	Only Recently Rising
New Caledonia	2	2	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Nicaragua	2	2	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Saint Lucia	2	0	0%	33%	New	New	New	Flat or Flattening	Flat or Near Flat
Sudan	2	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Zambia	2	2	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Angola	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Antigua and Barbuda	1	0	0%	0%	New	New	New	Flat or Flattening	Flat or Near Flat
Cabo Verde	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Chad	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Djibouti	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
El Salvador	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Eswatini	1	0	0%	0%	New	New	New	Flat or Flattening	Flat or Near Flat
Fiji	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Gambia	1	0	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Montserrat	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Nepal	1	0	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Niger	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Papua New Guinea	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Sint Maarten	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Somalia	1	0	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
St. Vincent Grenadines	1	0	0%	0%	New	New	New	Flat or Flattening	Flat or Near Flat
Vatican City	1	0	0%	0%	0%	0%	New	Flat or Flattening	Flat or Near Flat
Zimbabwe	1	1	New	New	New	New	New	Double in less than 2 days	Slope Falling or Constant
Total:	275,557	77379	34%	18%	19%	11%	8%	Double in 2-3 days	Rising vs (nearly) all periods

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About George Dorgan

George Dorgan (penname) predicted the end of the EUR/CHF peg at the CFA Society and at many occasions on SeekingAlpha.com and on this blog. Several Swiss and international financial advisors support the site. These firms aim to deliver independent advice from the often misleading mainstream of banks and asset managers. George is FinTech entrepreneur, financial author and alternative economist. He speak seven languages fluently.

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