hey guys, newbie here...
I couldn't find a way to pass cost per click to 
Can anyone real quick tell me how it's done?
Thanks!
To the best of my knowledge, this can't be done.
Decisive currently doesn't have the facility to pass cost-per-click to trackers.
Also, if you're using CPM (Cost per Mille, i.e. Cost per Thousand Clicks) or Smart CPM, the figures are actually for an average cost over each thousand clicks; so getting a specific cost-per-click isn't really practicable.
You can manually input an estimated CPC on Voluum, but currently you can't get cost-per-click from Decisive and you can't upload daily spend manually on Voluum.
Manual uploading of daily spend is a feature that Voluum are working on, so that's likely to change in the near future:
http://feedback.Voluum.com/forums/23...y-update-costs
Thank you! This indeed makes sense, I can't get actual CPC doing CPM bidding, doh 
ditto what @IanAtZen said. Can't pass cost at Decisive BUT here's everything you can pass:
http://help.decisive.is/knowledgebase/articles/277557
Macro Field Info
{{{bidhash}}} Unique impression ID (Use this to track conversions/actions)
{{{ad_id}}} Ad ID (Identifies the ad associated with the impression/click/conversion)
{{{creative_id}}} Creative ID (Identifies the creative used in the ad)
{{{ad_name}}} Name of campaign
{{{carrier}}} Carrier used by mobile device (Verizon, AT&T, T-Mobile, ...)
{{{os}}} OS of device (Android, iOS, BlackBerry OS, Windows Phone OS, ...)
{{{os_version}}} OS Version (Android 4.0.4, iOS 6.0.2, ...)
{{{device}}} Device type (iPad, DROID RAZR, Kindle Fire, ...)
{{{media}}} app or site
{{{country}}} Country of visitor (United States, Mexico, Canada, Germany, ...)
{{{ip}}} IP address of user
{{{app}}} Name of app where ad is placed
{{{site}}} Name of site where ad is placed
{{{placement}}} Combination of site and app. Name of either site or app where ad is placed.
{{{ua}}} User agent string
{{{category}}} IAB Category of site/app
{{{subcategory}}} IAB Subcategory of site/app
{{{idfa}}} iOS User IDFA