marker scaling on time series line charts

[ssuess]

I am having some trouble with marker scaling on a time series line chart with a variety of zoom levels. I have some annotations that are marker circles that I set with a size of 6, these sit above the series lines they fall on. And I am showing markers on the series lines only on hover, and I want the markers to be slightly larger on hover than the circle annotations, so I set them to be a size of 8. This works perfectly at some timescales, but at others the markers are either far too large or far to small relative to the annotation circles. I just want them to be always slightly larger than the annotations, but for the life of me can't get this to work. I have tried making the annotation circles a variable and the marker hover that variable + 2, but this also does not work. Anyone have any suggestions for how to maintain a consistently larger size than my annotations? Thanks!