Rather than "go back x days", I think it's much easier to see if it shows the date (e.g. Mar. 15th). Also, given that this is not really useful anymore, I'd set the default to be sometime early in the trajectory.

Yeah. It makes sense. I changed the format of "Go back to" to time, rather than numbers. Since time is something people might want to change in this visualization, I think it's better to show the date also within the chart. If you think it's unnecessary, I'll delete the date in the chart. As for the "Go back to", which do you think is better: the current one, or letting people adjust the date range (as is shown below)? Thank you so much for the helpful feedback! Hongtao

I'm not sure what are the two options that you're referring to.

Oh, sorry for the confusion. I am referring to 1) "Go back to" (above the comment); and 2) "Adjust the date range" (below the comment). Do you think it's a good idea to show the date within the chart? Also, I've updated the x-axis value. It now is a variable, which changes as people change the "Go back to" parameter.

Maybe having "go back to" is enough without the date range adjustment? I think it's useful to show the date given that it can travel back in time. I think having more double guidelines would be useful. Now spreading is much slower.

Yeah, I agree. 'Going back to' is enough. Otherwise, we need to show both the start date and the end date in the chart, which is not very nice. I also think it's better to show the date in the chart. I've set the default of "doubling guidelines" to be all the seven. Do you think I need to add "doubling every 8, 9, 10, 11, 12 ... days"?

I'd say 2, 3, 4 weeks?

Yeah. That's better. I've made the changes (could you check whether I did it right ?). I've also added a description so people will know what this parameter does.