Every day, three short rounds built from real historical data. Same puzzle for everyone.
1Draw the curve
You see the title and axes, but no line. Drag across the grid to draw what you think happened.
2Scale the axis
You see the curve, but the numbers are hidden. Turn the dial to guess the value at the marked point.
3Name the lines
Three unlabelled lines. Put each name on the line it belongs to.
Use of chlorofluorocarbons, weighted by how much each one damages the ozone layer.
ozone-depleting tonnes · 1986–2020
Use left and right arrows to pick a year, up and down arrows to set its value, Page Up and Page Down for bigger steps and Enter to lock in.
Drag across the grid to draw the curve. The first point is given.