formula used:
"■□□□ No Understanding: " + format(round(length(replaceAll(replaceAll(prop("Understanding"), "No Understanding", "§"), "[^§]", "")) / prop("No. Notes") * 100)) + "%"
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"■□□□ No Understanding: " + format(round(length(replaceAll(replaceAll(prop("Understanding"), "No Understanding", "§"), "[^§]", "")) / prop("No. Notes") * 100)) + "%"