Option 1: You have an existing GA (Google Analytics) account you want to keep using. You should upgrade your GA account to use UA (Universal Analytics).

<script>dataLayer = [{'channel' : ‘<insert project name here>’, ‘additional_tracking_code’ : ‘<insert optional additional GA tracking code here>'}];</script>
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<noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-NJWS5L"
height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
<script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
'//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
})(window,document,'script','dataLayer','GTM-NJWS5L');</script>
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