Network contraction between time steps

If I run a layout (Force Atlas 2 or 3D) while progressing the timeline, the network contracts dramatically between time steps. During the passage between time steps, edge weights appear to increase. I assume this is because Gephi is summing the edge weights for two time steps, but it happens even when I set the step size and intervals to the smallest possible value.

I used annual data to produce the graph for which an edge exists for the entirety of the year. So at some point during the evolution of the graph, the display interval straddles a portion two years, and during that point my assumption is that the layout sums the weights of both years.