I'm working on a web page with a series of charts that are built from visually-hidden HTML tables for accessibility - the idea being that the tables present the data in a form suitable for screen readers, and the data is rendered to SVG for visual web browsers.
It all works pretty well, but I'm wondering what the best way to accessibly specify units (effectively, the y-axis label) might be? Some of the tables / charts represent percentages, some represent frequencies, and some represent ages.
I suppose I could put the units in every element of the table so screen readers read, eg. "5 times per week", "3 times per week", but this seems very clunky. What I'd really like to do is specify units on, eg. the column header. Is there an accessible way to do this, though? Alternatively, would it be better to just specify the units in the table caption?