Not many words are needed here, the images, screen dumps from the website Flightradar24, tell their own story. The site calculated that the total amount of flights tracked on 25 March fell to 94,477 compared to 169,056 a year prior. Commercial flights accounted for 47,745 only, the lowest amount yet. A year earlier 106,895 commercial flights were recorded on the same day.
Just compare the visual from today and exactly one month ago:
Flight radar 27 March 2020 13:13
Flight radar 27 February 2020 13:05