I have always seen( since 1990s) that [the Fed](https://en.wikipedia.org/wiki/Federal_Reserve) changes( cut/increase) interest rates in [quarter point](https://www.barrons.com/articles/federal-reserve-interest-rates-investors-51564434394) increment /decrements in USA that affect the world bond, stock market and borrowing rates, while I see world news where the [ECB cuts by 10 points](https://www.cnbc.com/2019/07/18/european-central-bank-set-for-rate-cut-september-economists.html) and India by [unconventional 35 basis points](https://www.bloomberg.com/news/articles/2019-06-04/india-s-contrarian-economist-sees-35-basis-point-rate-cut) and [again](https://www.livemint.com/industry/banking/rbi-cuts-repo-rate-by-35-basis-points-maintains-accommodative-stance-1565155623580.html).

So what economics data is used by [the Fed](https://en.wikipedia.org/wiki/Federal_Reserve), and what mathematical operation ( [Monte Carlo](https://en.wikipedia.org/wiki/Monte_Carlo_method) ?) is done on the data, to arrive at quarter points result?.