One column per year, standing on the city. Orange is residents, teal is visitors on top.
*yellow* **red** ~teal~ Enter starts a new line.
Fields: {city} {country} {year} {pop} {visitors} {planes} {pax} {ships} {shippax} {total} {date} {time}
Put a * at the end of any number to mark that figure as an estimate.
Cities and countries both work, and fill in their own coordinates. Numbers can be typed any way you like: 3800000 or 3.800.000 both work.
Shared scale keeps every city on the same column height. Own scale lets each city fill its own frame.
The slider follows the mouse wheel too, so zoom the way you like it and it sticks. Both save with the setup.
Saves stay in this browser. Export data makes a file you can keep or move.