Math topic: Modeling

The number of films by genre grows roughly exponentially per year for many genres, with different rates per genre.

Sudden increase of carbon-14 from nuclear tests up to 1963. The atmospheric level has since decayed exponentially.

The number of feature films and TV movies with “Christmas” in the title doubled from 2011 to 2016, and doubled again from 2016 to 2021.

In a given country, the population of a city is inversely proportional to a power of the city’s rank by size in the country:

Data shows that since the 9th century, the date of the full flowering of Kyoto’s cherry trees happens about 4 days earlier every 70 years.