Zooming data with the drilldown feature
There are two ways to build an interactive drilldown chart: synchronous and asynchronous. The former method requires users to supply both top and detail levels of data in advance, and arrange both levels of data inside the configuration. Both levels of data are specified as standard Highcharts
series configs, except that the zoom-in series is located inside the
drilldown property. To join both levels, the top-level ...