Hubscores are calculated based on the number of visitors within a specific period of time, also originality of your hub. How many hubs you post is almost inconsequential. For example there are some hubbers that have been on the site for only weeks, have very few followers and even fewer hubs, yet they have a profile score in the nineties and similar hub scores. Quality and originality plus the number of visitors are the key points.
There are other factors, but they mostly apply to your profile score. However, the more hubs that you post the better chance of increasing scores by bringing in more visitors.
This is based on my own analysis for the last 2 months of all aspects, numbers,visitors, comments by others and other factors.