This is the legacy documentation for Google Ads scripts. Go to the current docs.

Declining Ad Groups Report - Single Account

Google Ads scripts can easily access statistics over multiple date ranges, and can therefore compare performance of campaigns through time.

Declining Ad Groups Report fetches ad groups whose performance we consider to be worsening:

The ad group is ENABLED and belongs to an ENABLED campaign, which means it’s serving.
Ad groups' Click Through Rate has been decreasing for three consecutive weeks.

Obviously, a more sophisticated measure of "worsening" may be developed.

The script outputs the data into a spreadsheet that looks like this:

Scheduling

The script uses three weeks worth of statistics to generate the report. It would make sense to schedule it Weekly.

Setup

Setup a spreadsheet-based script with the source code below. Use Declining Ad Groups Report template spreadsheet
Don't forget to update SPREADSHEET_URL in code.
Schedule the script Weekly.

Open the template spreadsheet.
Make a copy of the spreadsheet and save it:
- In the spreadsheet, menu, select "File -> Make a copy".
- Enter the new spreadsheet name, click "OK".
In Google Ads, navigate to Scripts.
Create a new script and give it a name; authorize the script.
Copy-paste source code into the script (see below).

Replace

var SPREADSHEET_URL = "[YOUR_URL]";

with

var SPREADSHEET_URL = "https://docs.google.com/...";

Use the URL of the spreadsheet created in step 2.

Save the script, click "Close".
If necessary, schedule the script.

Source code

// Copyright 2015, Google Inc. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

/**
 * @name Declining AdGroups
 *
 * @overview The Declining AdGroups script fetches ad groups in an advertiser
 *     account, whose performance is considered to be worsening. By default, ad
 *     groups whose Click Through Rate has been decreasing for three consecutive
 *     weeks is considered worsening. A more sophisticated measure of
 *     "worsening" may be developed if required. See
 *     https://developers.google.com/google-ads/scripts/docs/solutions/declining-adgroups
 *     for more details.
 *
 * @author Google Ads Scripts Team [adwords-scripts@googlegroups.com]
 *
 * @version 1.0.2
 *
 * @changelog
 * - version 1.0.2
 *   - Added validation for spreadsheet URL.
 * - version 1.0.1
 *   - Improvements to time zone handling.
 * - version 1.0
 *   - Released initial version.
 */

var SPREADSHEET_URL = 'YOUR_SPREADSHEET_URL';

function main() {
  Logger.log('Using spreadsheet - %s.', SPREADSHEET_URL);
  var spreadsheet = validateAndGetSpreadsheet(SPREADSHEET_URL);
  spreadsheet.setSpreadsheetTimeZone(AdsApp.currentAccount().getTimeZone());

  var sheet = spreadsheet.getSheets()[0];
  spreadsheet.getRangeByName('account_id').setValue(
      AdsApp.currentAccount().getCustomerId());
  sheet.getRange(1, 2, 1, 1).setValue('Date');
  sheet.getRange(1, 3, 1, 1).setValue(new Date());
  sheet.getRange(7, 1, sheet.getMaxRows() - 7, sheet.getMaxColumns()).clear();

  var adGroupsIterator = AdsApp.adGroups()
      .withCondition("Status = 'ENABLED'")
      .withCondition("CampaignStatus = 'ENABLED'")
      .forDateRange('LAST_7_DAYS')
      .orderBy('Ctr ASC')
      .withLimit(100)
      .get();

  var today = getDateStringInPast(0);
  var oneWeekAgo = getDateStringInPast(7);
  var twoWeeksAgo = getDateStringInPast(14);
  var threeWeeksAgo = getDateStringInPast(21);

  var reportRows = [];

  while (adGroupsIterator.hasNext()) {
    var adGroup = adGroupsIterator.next();
    // Let's look at the trend of the ad group's CTR.
    var statsThreeWeeksAgo = adGroup.getStatsFor(threeWeeksAgo, twoWeeksAgo);
    var statsTwoWeeksAgo = adGroup.getStatsFor(twoWeeksAgo, oneWeekAgo);
    var statsLastWeek = adGroup.getStatsFor(oneWeekAgo, today);

    // Week over week, the ad group is declining - record that!
    if (statsLastWeek.getCtr() < statsTwoWeeksAgo.getCtr() &&
        statsTwoWeeksAgo.getCtr() < statsThreeWeeksAgo.getCtr()) {
      reportRows.push([adGroup.getCampaign().getName(), adGroup.getName(),
          statsLastWeek.getCtr(), statsLastWeek.getCost(),
          statsTwoWeeksAgo.getCtr(), statsTwoWeeksAgo.getCost(),
          statsThreeWeeksAgo.getCtr(), statsThreeWeeksAgo.getCost()]);
    }
  }
  if (reportRows.length > 0) {
    sheet.getRange(7, 2, reportRows.length, 8).setValues(reportRows);
    sheet.getRange(7, 4, reportRows.length, 1).setNumberFormat('#0.00%');
    sheet.getRange(7, 6, reportRows.length, 1).setNumberFormat('#0.00%');
    sheet.getRange(7, 8, reportRows.length, 1).setNumberFormat('#0.00%');

    sheet.getRange(7, 5, reportRows.length, 1).setNumberFormat('#,##0.00');
    sheet.getRange(7, 7, reportRows.length, 1).setNumberFormat('#,##0.00');
    sheet.getRange(7, 9, reportRows.length, 1).setNumberFormat('#,##0.00');
  }

  var email = spreadsheet.getRangeByName('email').getValue();
  if (email) {
    var body = [];
    body.push('The Ctr of the following ad groups is declining over the ' +
        'last three weeks.\n');
    body.push('Full report at ' + SPREADSHEET_URL + '\n\n');
    for (var i = 0; i < reportRows.length; i++) {
      body.push(reportRows[i][0] + ' > ' + reportRows[i][1]);
      body.push('  ' + ctr(reportRows[i][6]) + ' > ' + ctr(reportRows[i][4]) +
          ' > ' + ctr(reportRows[i][2]) + '\n');
    }
    MailApp.sendEmail(email, '' +
        reportRows.length + ' ad groups are declining in Google Ads account ' +
        AdsApp.currentAccount().getCustomerId(), body.join('\n'));
  }
}

function ctr(number) {
  return parseInt(number * 10000) / 10000 + '%';
}

// Returns YYYYMMDD-formatted date.
function getDateStringInPast(numDays, date) {
  date = date || new Date();
  var MILLIS_PER_DAY = 1000 * 60 * 60 * 24;
  var past = new Date(date.getTime() - numDays * MILLIS_PER_DAY);
  return getDateStringInTimeZone('yyyyMMdd', past);
}

function getDateStringInTimeZone(format, date, timeZone) {
  date = date || new Date();
  timeZone = timeZone || AdsApp.currentAccount().getTimeZone();
  return Utilities.formatDate(date, timeZone, format);
}

/**
 * Validates the provided spreadsheet URL
 * to make sure that it's set up properly. Throws a descriptive error message
 * if validation fails.
 *
 * @param {string} spreadsheeturl The URL of the spreadsheet to open.
 * @return {Spreadsheet} The spreadsheet object itself, fetched from the URL.
 * @throws {Error} If the spreadsheet URL hasn't been set
 */
function validateAndGetSpreadsheet(spreadsheeturl) {
  if (spreadsheeturl == 'YOUR_SPREADSHEET_URL') {
    throw new Error('Please specify a valid Spreadsheet URL. You can find' +
        ' a link to a template in the associated guide for this script.');
  }
  return SpreadsheetApp.openByUrl(spreadsheeturl);
}

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