Suppose I have create a chart with fixed y axis (from -4 to 4), Instead of displaying numeric value on the y axis label, i will need to change it to other strings like : -4 -> -4σ -3 -> -3σ -2 -> -2σ -1 -> σ 0 ->x̄ 1 -> σ 2->2σ 3->3σ 4->4σ It would be nice if it can format the value of each Axis label (particularly for fixed max and min value)