Marketers are seeing a solid return on investment into paid advertising on social media, according to a new report from eMarketer. Executives from 29 companies scored social media advertising from several platforms, giving an average grade of B. Facebook and Pinterest received the highest grades, with Facebook earning a B+ and Pinterest a B.

“Marketers consider Facebook an extremely sophisticated targeted advertising platform, while Pinterest benefits from its strong connections with e-commerce and purchase intent,” said Debra Aho Williamson, principal analyst at eMarketer.

Marketers graded the ‘Big Three’ networks – Facebook, LinkedIn and Twitter – and the ‘Emerging Three’ – Instagram, Pinterest and Snapchat – in a range of categories, including creative capabilities, ad targeting, measurement and ROI. Though paid advertising received an overall B grade, marketers said they want better tools to gauge the effectiveness of social media advertising on their bottom line.

LinkedIn received high marks for ad targeting, earning a B, but in other categories its marks were lower. Twitter performed strongly in creative, ad targeting, measurement and analytics, building brand awareness, and engagement and driving actions, all of which earned a B. Instagram received the highest grades among the ‘Emerging Three’ for creative and building brand awareness and engagement.