When I do
ListPlot[Table[RandomReal[NormalDistribution[], {20, 2}], {2}],
PlotStyle -> PointSize[0.02],
Epilog ->
Style[Text["b: 5%", Scaled[{0.05, 0.05}], {-1, -1}],
FontFamily -> "Helvetica"]]
the percent symbol is shown in the wrong typeface, possibly Times. How can I make it display in the correct face?