This demonstration is based upon Carl Sagan's "Cosmic Timeline" for the Universe, except we will start with the formation of our planet as Jan 1, 2020 at 12:00am. Sample calculation: The Precambrian Era lasted from 4.56 Ga to 570 Ma (equivalently = 4560 Ma to 570 Ma) Each calendar day (there are 366 days in 2020) represents 12,459,016 years (equivalently ~12.459 Ma) We need to represent 3990 million years (from 4560 million -570 million). This works out to 320.25 of our 366 available days! The Precambrian would have lasted from Jan 1, 2020 all the way until Nov 15th, 2020!