I’ve included links above, if you want to see the numbers and the graphs from Hubspot.com. Hubspot.com is an internet marketing training and software company and they did the research on their blogging vs. non-blogging clients. Since the businesses in the survey are Hubspot.com clients, you can assume most or all of these websites have good use of keywords and calls to action. These websites are better than your run-of-the-mill vanity site.
I’ve been recommending my clients blog weekly or twice weekly. The reason being adding content to your website frequently and consistently increases your visibility with Google. As time goes by it also adds link backs or links to your site.
However, after reading these studies I’m more likely to recommend daily blogging. If you are running an online business, you’ll want to make time for daily blogging. If your company has a team or group, you might consider asking each team member to write a weekly blog post and assign them a day to upload it. A reasonable goal would be get to 100-200 posts rapidly while maintaining quality.