option = {
    tooltip: {
        formatter: '{a} <br/>{b} : {c}%'
    },
    toolbox: {
        feature: {
            restore: {},
            saveAsImage: {}
        }
    },
    series: [
        {
            name: '业务指标',
            type: 'gauge',
            detail: {formatter: '{value}%'},
            data: [{value: 50, name: '完成率'}]
        }
    ]
};

setInterval(function () {
    option.series[0].data[0].value = (Math.random() * 100).toFixed(2) - 0;
    myChart.setOption(option, true);
},2000);