If its only a bar you want to animate you can just build it and animate it using code. The Symbol Progress approach is only needed if you want to animate the progress (time property itself). Makes most sense for complex animations where the progress is some sort of indicator.
Something elementary with data is the following… but it doesn't use symbols.
Data can also be defined in window (Head HTML) outside of Hype.
safetyPercent-Maxv2.hype.zip (176,2 KB)