Google Chart Date Drill down repeating same bars

Hello,
 
We are using google charts with flexmonster integration. I am attaching a screenshot of what's happening.
If you see the screen shot , I have `year/quarter/month/day` in row , when I drill down to quarters, months, days, for every drilldown step if you see the chart the same bars are repeated, which is seems to redundant. Is there is away to avoid that ? Could you please help us out ? 
 
BTW. Here is my prep function.
    private prepareDataFunction = (report, options) => {
        const output = {} as any;
        const table = [];
        const cAmount = report.meta ? report.meta.cAmount : 0;
        for (let i = 0; i < report.data.length; i++) {
            if (i === 0) {
                const xAxisName = (report.meta.r0Name !== undefined) ? report.meta.r0Name : '';
                const headerRow = [xAxisName];
                table.push(headerRow);
            }
            const record = report.data[i];
            if (record.r0 === undefined && record.c0 !== undefined && record.v0 !== undefined) {
                let label = record.c0;
                for (let j = 1; j < cAmount; j++) {
                    label = record[`c${j}`] ? label + ` - ${record[`c${j}`]}` : label;
                }
                table[0].push(label);
            }
            if (record.r0 === undefined || record.c0 === undefined || record.v0 === undefined) {
                continue;
            }
            // tslint:disable: variable-name
            let _record = table[table.length - 1];
            if (record.r0 === _record[0]) {
                _record.push(record.v0);
            } else {
                _record = [record.r0];
                _record.push(record.v0);
                table.push(_record);
            }
        }
        output.data = table;
        output.options = {
            title: ''
        };
        return output;
    }