About adding units to the angular-charts on the X-axis and Y-axis.

[Wjp43045]

I find that the X-axis and Y-axis of the angular-charts have no units, so how do I add them? thanks a lot.

<canvas id="line" class="chart chart-line" data="data.charts.lineData" labels="data.charts.lineLabels" legend="true" series="series" options="{showTooltips: false}"></canvas>