Returns the numeric value for a specific label in a specific Breakdown. This enabled direct access to and extraction of values from BreakdownSets as a convenience of using Breakdown metadata in the calculation of KPI values.
var invoices = metrics.getLatest('Invoices');
var breakdown = invoices.breakdown();
var total = invoices.sum();
var subscriptions = breakdown.valueOf('Account*', 'Subscriptions');
return (subscriptions / total) * 100;