This will be a lot easier to do if you swap the layout.

Put the time in a column to the right of the mean values. If you don't
want to mess your existing data set, use a copy.

Now, plot a XY Scatter chart using a subtype that includes a line. The
means will be on the x-axis and the times will be on the y-axis.

Now, double-click plotted series, then select the 'X Error Bars' tab.
In there, in the Display section select the 'Both' option. In the
'Error Amount' section, select the Custom option. For both the + and -
values specify the same standard deviation values you have.

--
Regards,

Tushar Mehta, MS MVP -- Excel
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
Custom MS Office productivity solutions

In article , says...
Hi

Could anybody help me on this: I want to plot the mean and standard
deviation as a function of, say, time (I know that it will be discrete
in time), with the mean marked with a dot and mean+standard deviation as
a short horizontal line, connected to the mean-dot by a vertical line
and mean-standard deviation the same way.

It may be what is called a box plot, but I'm not sure...

Thank you!
/Mette