Who decides the economic event impact level, is it by the website? because I see the same event is (high) in website and (medium impact) in other
Quite often those are some self proclaimed bs rating agencies. Like those from 08 who gave triple A's to those junk CDOs loans (?) (Forgot the symbol). Then there's Zacks etc. Maybe it derives from the average rating scores of multiple economists. Yet those might be biased as well. Bribed etc. Anyway, Warren placed it well : ,,Never seen a wealthy economist in my life" Peter Lynch : ,,If you spend 15 mins. reading about economy, then you just wasted 13 mins"
thank you, i meant the events in the forex calendar, some events are 3 stars (high impact) on one of these fx calendar website and "low impact" in another
Actually Warren is a bit wrong on that. John Maynard Keynes, the founder of Keynesian Economics was very wealthy and was a very successful investor during his lifetime. His fortune was almost completely wiped out during the stock market crash of 1929 and he recouped almost all of it back and died a multi-millionaire despite being a philanthropist supporting numerous charities and not-for-profit organizations. Warren himself actually mentioned Keynes when talking about investing.
It depends on the historical volatility on those events whether they are low or high impact I would say. See illustration below therefore.
They change also. During the inflation and Feds tightening time like what we are experiencing now, it would be the CPI and the FOMC events that would be more market-moving. During recession times when there is higher unemployment, it would be the NFP that people would pay more attention to.
You do it yourself, by spending years of studying how the market/instrument reacts to specific events. For example, the quarterly Wednesday crop reports in wheat are high-priority if you trade wheat futures, but low impact if you trade equity indices. The weekly NG reports on storage can be a high-impact event if you trade NG futures, but low impact if you trade lumber.