Creating a chart using data from several sheets

main.gs

function delAllChartsFromSheet(name)
{
  var ss = SpreadsheetApp.getActive();
  var sh = ss.getSheetByName(name);
  var chts = sh.getCharts();
 
  for (var i = 0; i < chts.length; i++)
  {
    sh.removeChart(chts[i]);
  }
}
function addArrayToSheetColumn(sheet, column, row, values)
{
  const range = [column, row, ":", column, (parseInt(row) + values.length - 1).toString()].join("");
  const fn = function(v) {
    return [ v ];
  };
  sheet.getRange(range).setValues(values.map(fn));
  return range;
}
function myFunction()
{
  var sheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName('Главная');
 
  delAllChartsFromSheet("Главная");
 
  var sheetNames = [];
  var data = [];

  var max = -100000, min = 100000, mean = 0, cnt = 0;
  var maxMonth = null, minMonth = null;

  var spreadSheetsInA = SpreadsheetApp.getActiveSpreadsheet().getSheets();
  
  for (var i = 0; i < spreadSheetsInA.length; i++)
  {
    if ((spreadSheetsInA[i].getName() != 'Главная') && (spreadSheetsInA[i].getName() != 'Шаблон 30 дней') && (spreadSheetsInA[i].getName() != 'Шаблон 31 день'))
    {
      var tempSheetName = spreadSheetsInA[i].getName();
      var tempSheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName(tempSheetName);
      sheetNames.push(tempSheetName);
      data.push(tempSheet.getRange('B11').getValue());

      mean += tempSheet.getRange('B11').getValue();
      if (tempSheet.getRange('B11').getValue() > max)
      {
        max = tempSheet.getRange('B11').getValue();
        maxMonth = tempSheetName;
      }
      if (tempSheet.getRange('B11').getValue() < min)
      {
        min = tempSheet.getRange('B11').getValue();
        minMonth = tempSheetName;
      }
      cnt++;
    }
  }
  
  var start = "100"; // starting row for temp data

  addArrayToSheetColumn(sheet, "A", start, sheetNames);
  addArrayToSheetColumn(sheet, "B", start, data);

  var chart = sheet.newChart()
  .setChartType(Charts.ChartType.LINE)
  .setPosition(6, 2, 0, 0)
  .setOption('title', 'Траты')
  .setOption('vAxis', {'title': 'Рубли'})
  .setOption('hAxis', {'title': 'Месяцы'})
  .addRange(sheet.getRange(["A", start, ":", "B", (parseInt(start) + data.length - 1).toString()].join("")))
  .build();

  sheet.insertChart(chart);

  sheet.getRange("B2").setValue([max]);
  sheet.getRange("B3").setValue([min]);
  sheet.getRange("B4").setValue([mean / cnt]);
  sheet.getRange("C2").setValue([maxMonth]);
  sheet.getRange("C3").setValue([minMonth]);
}