I use the spread function a lot. This function must cause lots of calculations, especially when associated with categories. Usually I spread the values in one time series across a series of months - but this series is usually short, perhaps 10 months. So that SpreadVariable has 10 numbers (percentages that add up to 100%) followed by all zeroes. For example, I might have calculated the number of sales I will achieve from a sequence of sales activities. However the sales will not all occur in the first month. So I set up a sequence of ten numbers that add to 100% and spread the sales out accordingly. I usually don’t know I will have exactly ten percentage values for certain, so I use the notation: SpreadVariable[0:t]. But this means the spread calculation will keep multiplying for all the months in the span of my model. You may already do this, but if not, I suggest that you check the spread variable to see if it goes to zero for the rest of the time range and if so, cut off the calculations. If you already do this, please let me know, if not, checking for zeros might result in a big performance improvement.

Another challenge with spread functions is that if you only have 10 numbers that you care about (as w/ wiver’s example, and you have your model set to only show a subset of months, you can’t see those 10 numbers if the first 10 months are not shown. This can be painful / confusing if you use spread but frequently hide some of the earliest (historical) months in a model.

Have you tried setting the format for the spreadvariable to “relative time”? Then maybe it will stay visible. I have not tested this.