Tracking Conversion - Google Analytics + Adwords Conversions

[jaffstar]

I am trying to track conversions from Adwords and Google Analytics.

I have setup thank-you pages to trigger conversions.

Do I need to install the Google Analytics code As well as the Adwords lead conversion code on thank-you page?

For some reason, I am under reading conversions. If one customer submits an enquiry and a quote request, could this cause it to only read two conversions as one person?

[BradleyT]

Yes you need both codes on the page.

Analytics for normal data and AdWords tracking code to fire off a conversion.

We use a similar setup.