Facebook today increased the size of its IPO again, which could bring in up to $16 billion, according to reports.

The change, outlined in a filing with the Securities and Exchange Commission (SEC), comes one day after General Motors confirmed plans to drop advertising from the site. This $10 million loss is certainly unwelcome news for the social network, which - according to a new infographic from WordStream - trails far behind Google in the online ad space.

According to WordStream, Google has an advertising click-through rate of 0.4 per cent, which is "10 times as high as the typical Facebook ad," where it's under .05 per cent. "So far, Facebook's advertising platform hasn't kept pace with the explosive growth of its social network, and it remains to be seen if CEO Mark Zuckerberg even wants to focus on advertising as a source of revenue. In his 2,500+ word letter to shareholders this month, he mentioned advertising just once," Larry Kim, founder and CTO of WordStream, said in a statement.

One major area where Facebook plans to focus its money-making efforts in the coming years is mobile. When the social network's IPO was announced in February, Facebook revealed that it had 425 million mobile users, but was not yet making any money from them. By March, that number had grown to 488 million, but still no revenue. The world's largest social network is also on track to become the first online entity with one billion registered users.

Published under license from Ziff Davis, Inc., New York, All rights reserved. Copyright © 2012 Ziff Davis, Inc.