Update: After careful consideration and debate with @estebanbianchi we reached the conclusion that this coefficient is totally useless. However, we agree on the importance of having a way to identify really useful open government data, contrasting these efforts with those who only do it for show.

I propose a number that tells me if a Government truly believes in opening its sensitive data or if it’s just opening non-sensitive data.

The coefficient is the amount of data sets that involve monetary amounts payed by the government over the total amount of data sets.

As an example, let’s say that Elbonia publishes 560 datasets, of which 13 have monetary amounts payed by the Government.
Its Orihuela coefficient would be 0,02.

The bigger the number, the more disclosure.

If the government of Transparentia has 160 datasets, of which 80 show amounts payed by the Government, the Orihuela coefficient would be 0,5.

Of course, this coefficient should be used as a heuristic (rule of thumb) and never considered as an accurate determination of the level of transparency of a government.

Original photo: https://www.flickr.com/photos/erikbenson/3835146379/