These are some minor adjustments to the google-charts element from mmathias01 (https://github.com/mmathias01/google-charts), trying to get it working with Polymer 3. The readme was not updated and is still the one from the original google-charts element!

google-charts

ES6 Google Charts Module that allows asynchronous loading

Installation

yarn add -D google-charts

or

npm i -D google-charts

Quick Start

import {GoogleCharts} from 'google-charts';

//Load the charts library with a callback
GoogleCharts.load(drawChart);

function drawChart() {

    // Standard google charts functionality is available as GoogleCharts.api after load
    const data = GoogleCharts.api.visualization.arrayToDataTable([
        ['Chart thing', 'Chart amount'],
        ['Lorem ipsum', 60],
        ['Dolor sit', 22],
        ['Sit amet', 18]
    ]);
    const pie_1_chart = new GoogleCharts.api.visualization.PieChart(document.getElementById('chart1'));
    pie_1_chart.draw(data);
}

Advanced Usage

import {GoogleCharts} from 'google-charts';

//Load the 'corecharts'. You do not need to provide that as a type.
GoogleCharts.load(drawCharts);

/* 
* Load a specific type(s) of chart(s). You can call this as many times as you need from anywhere in your app
* GoogleCharts is a singleton and will not allow the script to be loaded more than once
*/
GoogleCharts.load(drawGeoChart, 'geochart');

function drawCharts() {

    /* Pie chart 1 */
    const pie_1_data = GoogleCharts.api.visualization.arrayToDataTable([
        ['Chart thing', 'Chart amount'],
        ['Lorem ipsum', 60],
        ['Dolor sit', 22],
        ['Sit amet', 18]
    ]);
    const pie_1_options = {
        pieHole: 0.8,
        pieSliceTextStyle: {
            color: 'black',
        },
        slices: {
            0: {color: '#7ec252'},
            1: {color: '#a4ce57'},
            2: {color: '#cfe4ad'}
        },
        legend: {
            position: 'bottom',
            textStyle: {
                color: 'black',
                fontSize: 13,
                fontName: 'EncodeSans'
            }
        },
        title: 'Chart 1',
        titleTextStyle: {
            color: 'black',
            fontSize: 13,
            fontName: 'EncodeSans'
        },
        chartArea: {left: 0, top: 0, width: '100%', height: '80%'},
        pieSliceText: 'none'
    };
    const pie_1_chart = new GoogleCharts.api.visualization.PieChart(document.getElementById('chart1'));
    pie_1_chart.draw(pie_1_data, pie_1_options);

    /* Column chart 1 */
    const col_1_data = GoogleCharts.api.visualization.arrayToDataTable([
        ['Chart 1', 'Lorem ipsum', 'Dolor sit', 'Sit amet'],
        ['Chart 1', 22, 10, 68]
    ]);
    
    const col_1_options = {
        legend: {
            position: 'bottom',
            textStyle: {
                color: 'black',
                fontSize: 13,
                fontName: 'EncodeSans'
            }
        },
        bar: {groupWidth: '25%'},
        colors: ['#808e97', '#b9c3ca', '#dde4e8'],
        isStacked: true,
        chartArea: {left: 0, top: 0, width: '100%', height: '80%'},
        axisTitlesPosition: 'none',
        hAxis: {textPosition: 'none', gridlines: {color: 'transparent'}, baselineColor: 'transparent'},
        vAxis: {textPosition: 'none', gridlines: {color: 'transparent'}, baselineColor: 'transparent'},
    };
    
    const col_1_chart = new GoogleCharts.api.visualization.ColumnChart(document.getElementById('chart2'));
    col_1_chart.draw(col_1_data, col_1_options);
}

function drawGeoChart() {

    /* Geo Chart */
    const geo_1_data = GoogleCharts.api.visualization.arrayToDataTable([
        ['State', 'Spend'],
        ['ID', {v:120000, f: '$120,000'}],
        ['CO', {v:567135, f: '$567,135'}],
        ['FL', {v:220000, f: '$220,000'}],
        ['NY', {v:1120000, f: '$1,120,000'}],
        ['CA', {v:5120000, f: '$5,120,000'}],
        ['AK', {v:101000, f: '$101,000'}],
        ['AZ', {v:311030, f: '$311,030'}]
    ]);
    const geo_1_options = {
        region: 'US',
        resolution: 'provinces',
        is3D: true,
        legend: {
            numberFormat:'$###,###'
        }
    }
    const geo_1_chart = new GoogleCharts.api.visualization.GeoChart(document.getElementById('geo_1_chart'));
    geo_1_chart.draw(geo_1_data, geo_1_options);
}