Desktop accounts for 70% of paid search spend

"Desk­tops now rep­re­sent 70% of paid search (com­pared to 77% in August 2013) while mobile/smartphones account for 30%. Cur­rent trends indi­cate that the share for desk­tops will con­tinue to decline and hit 60% of paid search by the end of 2014 due to the organic increase of smart­phone adop­tion. The uptick in smart­phone adop­tion and usage can be attrib­uted to bet­ter WiFi avail­abil­ity, greater mobile data band­width, and improved mobile land­ing pages, site and app expe­ri­ences con­ducive to bet­ter facil­i­tate mobile shop­ping. For the UK, mobile adop­tion has out­paced the U.S. (64%) with desk­tops only account­ing for 56% of all paid search spend. Tablets account for a quar­ter of all search spend and mobile rose to almost 20% (from just 11% ten months earlier)."
Source:  Data from Adobe, reported on it's blog, 16th July 2014
Methodology
"Based on adver­tiser data across key ver­ti­cals in the U.S., U.K. and Ger­many, we looked at the var­i­ous ad for­mats from Google includ­ing Prod­uct List­ing Ads (PLAs) – which are becom­ing part of Google Shop­ping – to see how they’re per­form­ing for adver­tis­ers. The analy­sis is based on the most com­pre­hen­sive set of indus­try data includ­ing $2+ bil­lion of annual man­aged search spend of 500+ Adobe Media Opti­mizer cus­tomers and 200+ bil­lion search impressions."
Note - lots more data in the blog post