Some very basic analysis based on the figures available from wikipedia.
You can find the previous three parts of the analysis here:
Italy, Spain, and France:
https://hive.blog/coronavirus/@miniature-tiger/coronavirus-analysis-part-2-italy-spain-and-france-are-the-lockdowns-working
Germany and UK:
https://hive.blog/hive-196427/@miniature-tiger/coronavirus-analysis-part-3-germany-and-uk-why-are-death-rates-so-much-lower-in-germany
In this post I look at the coronavirus figures for the USA.
New York and New Jersey
The USA is fast approaching half a million reported cases of coronavirus, almost 30% of the worldwide total. The states hardest hit have been New York and New Jersey.
The two states entered lockdown at almost the same time with stay-at-home orders issued on 21 March for New Jersey and 22 March for New York.
Here are the charts of new cases and deaths by date for each state with the lockdown date highlighted.
New York:
New Jersey:
The coronavirus figures appear to be following the typical pattern we have seen in European countries. There is a levelling-off of the number of new cases per day occurring after two weeks of lockdown but the number of daily deaths continues to rise into the third week.
Using the European countries as a guide, from here I would expect to see a slow descent in the number of new cases per day for these states and a peak in the number of deaths per day towards the end of the third week of lockdown.
All other states combined
New York and New Jersey currently have 211k reported cases between them. All other states combined have 248k.
The stay-at-home orders were issues on different dates for different states. Some states acted at a similar time to NY and NJ. For states with later outbreaks, such as Florida and Texas, orders were issued at the start of April. The pattern of figures for other states combined is thus likely to lag those for NY and NJ by a week or so.
Here are the charts for all other states combined:
As can be seen, the pattern of new cases is starting to level off but is not as flat as for NY and NJ. The number of deaths continues to rise and is likely to do so for another week or two.
USA
Charts for the USA as a whole:
The overall country chart for new cases is likely to see a "rolling apex" as the outbreaks in different states work through their lockdown periods.
Conclusions
As in Europe, the stay-at-home / lockdowns appear to be having an effect with a flattening of the new cases curve clear in both New York and New Jersey.
The number of deaths could reach a peak within the next week for these states, if the pattern for Italy and Spain is followed.
Some other states are a week or so behind in their lockdowns. This will likely cause a "rolling apex" for new cases at a country level and thus a longer period before the number of cases clearly declines than for other countries.
Lifting of restrictions will most likely be on a state-by-state basis to reflect these differences in timing.
Sources:
https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_the_United_States
https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_New_York_(state)
https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_New_Jersey