This graph represent a Van Westendorp Pricing Sensitivity Analysis. We looked at over 1100 responses to the Drupal Association membership pricing survey and determined the optimal pricing point for individuals to be $30.

The optimal point is the intersection of too cheap and too expensive, in an attempt to maximize the number of purchasers of Drupal Association individual memberships.

Drupal.org has more than 150 000 members and the hope would be that this price would optimize the number of individual memberships purchased.

The data was normalized to a constant currency of US dollars from Euro and US responses. Responses of 0 or less were discarded as they began to skew the pricing sensitivity very low. Data was collected for over a month and a sample size of over 400 responses is very good.

An attempt to calculate a likelyhood of purchasing was very difficult and we could only use clustering to determine if this was a valid price, likely to be purchased.

Further statistical techniques such as normalization, or six sigma could have been used as well.

See the attached graph.