I have a panel data set and each observation is identified by an ID and a date. For example, there are 100 firms and 120 monthly observations for each firm.

I want to plot monthly cross-sectional averages and cross-sectional standard deviations for 2 variables in a single figure. The standard deviations should be shown in a similar way as confidence intervals in -coefplot-. From what I attempted, -xtgraph- does not allow -twoway-. Is there a good solution for this goal?