All days with abnormally high case counts were usually Mondays. No Saturday or Sunday in the report. This means Mondays contain 3 days worth of new cases.

select *from (select country_region, date, confirmed, deaths,LAG(confirmed, 1) OVER (PARTITION BY country_region ORDER BY date ASC) AS prev_day,confirmed - LAG(confirmed, 1) OVER (PARTITION BY country_region ORDER BY date ASC) as new_casesfrom `bigquery-public-data.covid19_jhu_csse.summary`WHERE…