How can I populate data from Google Spreadsheet?
Go to your Google Drive and create a new spreadsheet document.
The first line of the spreadsheet should contain the series titles. The second line of the spreadsheet must contain the type of series’ data. You may use one of six data types: string, number, boolean, date, time date, and time of day. The other lines need to contain data values according to the data type chosen.
After you enter your data, save the spreadsheet and click on "File" > "Publish to the Web…" menu item.
In the new dialog, you need to click the "Start publishing" button. A link to the published item appears in the publishing dialog.
Choose "CSV (comma-separated values)" type and select the box below "Get a link to published data" sub header and copy link to the published spreadsheet at the text area below.
After you've published your spreadsheet, create a new chart or edit existing one and go to the second step, which allows you to upload your CSV file. Expand the "Import data from URL" sidebar menu and click on the "One time import" menu. Then enter the published link into the URL field and click "Import". After you have entered the link, it will be automatically uploaded and a chart preview with the data will be updated.