Can you shade in trend line

My data is all over the place. When I trend it it looks better. This data is only a simulation so the trend works great, but it's only a line.....my real graph is shaded in and I like that feature but the data is too volatile, too many peaks and valleys.

Anyway i can make the trend data have something under it (shaded area under it)????

The data size is huge, too hard to go in an manually change the values and too big to make as an attachment unless I delete some data.