Add proportions for NHSN

[aysim319]

Due to time constraint the main metric that would be available once nhsn is deployed is raw counts. However, due to the reporting mandate not being consistent; the number of reporting hospital should be considered.

This was mentioned in previous iterations, but at the time was not a factor as normalizing the data would result in noise and therefore would not add consider number of reporting hospitals.

At the final stages of implementing the indicator, it was decided that the proprotions should be added, but in a future release in order prevent more delays in initial release of nhsn