You can click the colorful indicator in the legend to hide that column. I believe this persists when the look is saved. Not exactly what you want, but hopefully helpful.

@weitzenfeld and @herdrick: You can convert any dimension to a computed measure by including a measure in the computation. For example, if you have a measure count and a dimension year, you can make a computed measure by adding and subtracting count ...

Readers should note that this UI is now possible not only for type: time dimensions: see Grouping Fields Within Views (3.44+).

It would be nice to be able to extend dashboard elements. For example, say a dashboard should have multiple elements reflecting time spans, an extension could look like the following. (The names in this LookML fragment are not actual names from my co...

Note that if your rows are reversed and you want the rolling average to be for the rows preceding the current one, the second argument to offset_list will need to be negative. In the above example, that would be: mean(offset_list(${orders.count}, -6,...