How do I group trace names similar to legendgroup in hoverinfo?

I have created a filled chart with grouped legends. Two of the legends are min - max values, listed in each column “Min” and “Max” in the CSV file. I am trying to group these values in hoverinfo, logically this would be done similar to legendgroup, but I can’t seem to find the answer anywhere and when searching for it, I only see very simple examples for hoverinfo in plotly’s own documentation.
So for example for x = 1960, y = Min - Max: -0.24 - -0.19 should be listed in the hoverinfo tooltip. But currently the min value is a separate number.

The chart :

https://plot.ly/~marialaustsen/2/pip-install-plotly-upgrade/#/

Thanks for the help!