You have an advertiser on your website requesting statistics for their ads. Fair enough, they're probably paying pretty dollar and don't trust two-bit developers ;)

COMMON ANSWER FOR COMMON ADVERTISER REQUESTS

• Make the stats publicaly accessible
• Give advertiser access to the web stats account (i.e. Google Analytics)
• Installing their own code on the website

THE HOLY SOLUTION

Create a new profile to share specific page stats from your parent Google Analytics account.

Steps

1. Login to Google Analytics.
2. In the "Overview" page, click "add new profile" as displayed to the right of your chosen account.
3. Select "Add a Profile for an existing domain" and complete remainder of form as usual.
4. Select "Edit" on the recently created profile in "Overview" page.
5. Click "Add Filter".
6. Select "Custom Filter".
7. Select "Include".
8. Select "Filter Field" to be "Request URI".
9. Use the following code to filter by matching strings to the URI.
   • Example 1: show stats only for contact.html
     ^.*\b(contact)\b.*$
   • Example 2: show stats only for contact.html or about.html
     ^.*\b(contact|about)\b.*$
     
10. Use the Google Analytics Regex Filter Tester if needed.
11. Save the filter.
12. Click "Add User" in "Profile Settings" page.
13. Add user to "View reports only".
14. Have a well deserved drink and wallow in glory!
    

Benefits:

• For You:
  1. The user will be given access via a Google Analytics account. Therefore, information is not public.
  2. Access to real-time rather than batched data
  3. Use your existing tracking code
  4. No additional 3rd party code (better load times)
  5. Instant control of 3rd party's access to Google Analytics account.
• For 3rd Party:
  1. The 3rd party can generate their own stats reports.
  2. Access to real-time rather than batched data
  3. Perceived transperancy on your behalf

Disadvantages:

• For You:
  1. Solution does not show historic data, only from when the profile is created.
• For 3rd Party:
  1. This solution is only for Google Analytics. 3rd party will need to export data into other statistic packages if consolidated data is required.

Continual Development

Any suggestions for improvement are much appreciated. Let's hope in the future, Google Analytics will have similar functionality by default.

Source : Sharing Google Analytics data with 3rd Parties