The short answer is: it depends on the goals you're trying to achieve. If you're simply looking to stay relevant and drive brand awareness, one to two blog posts a week and a quarterly gated ebook or white paper may be sufficient. If you’re starting a new blog and want to establish a foothold quickly, you'll want to fire on all cylinders, not only publishing tons of content on your own site but also guest blogging on other sites that target your audience to spread your reach.