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1. Download the latest version of the plugin from the Atlassian Marketplace

2. Log in as an user with Confluence Administrator role

3. Go to Confluence Administration Console by clicking on the Browse -> Confluence Admin in the top menu bar

4. On the left sidebar, click on Manage Add-ons link under the Add-ons section

5. Click on the Upload Plugin link to bring up the Upload Plugin dialog box

6. Click on the Browse button and select the jar file that you have downloaded previously 

7. Click on the Upload button to upload the plugin

8. Click on the Close button to acknowledge

Configuration

A license key is required for the plugin to work. 

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To update the license key

1. Log in as an user with Confluence Administrator role

2. Go to Confluence Administration Console by clicking on the Browse -> Confluence Admin in the top menu bar

3. On the left sidebar, click on Manage Add-ons link under the Add-ons section

4. Search for the Site Statistics for Jira under the User-installed Plugins

5. Click on it once to expand the details

6. Paste the license key and click on the Update button