formatter: function (params, ticket, callback) {
let str = '';
str += params[0]['name'];
for (let i in params) {
str += '\n';
str += '{marker' + i + 'at0|} ';
str += params[i]['seriesName'];
str += ':'
str += i == 3 ? (params[i]['value'] + '%') : params[i]['value'];
}
return str;
},