I've seen this implemented as tooltips where you hover your mouse over a label and the additional information is shown in a little popup window. Chart labels themselves are succinct and don't lend themselves to displaying a lot of details. I know that tooltips are possible with Chart.js, but I don't know if you can do this with the Google charts that Formidable generates. Figuring this out requires having someone looking into Formidable's source code. If you're comfortable doing that, you're looking for any clue that indicates you can use tooltips with Google charts.