Create a line chart to express rate

Hi, can anyone help me figure out how to add a percentage rate to a chart? I have a list of candidates who took a test, some passed some failed. I want a line graph, tracking pass rate = %pass/total with the date on the x axis.

Also additionally, is it possible to have two lines on the same line chart? Like pass rate by background and one line for each background?

Trying to bump this up again, any help would be really appreciated :slight_smile: