Recently i was present with a task estimation technique. Instead of letting people rate a task for x-amount of hours, let them discretize a tasks into discrete sizes like small/medium/large/x-large. (Planning poker from scrum for people aware of this)

After a bit of tracking we should be able to estimate the duration based upon historical data (i.e. statistics)
I have been given a set of sample data (real data, but not from my work) and would like see there actually can be made any distribution which fit this. (of course i would need to recalculate this for my on tasks)

The distributions from the presentations look like this:![enter image description here][1]

It seem like some right skewed distribution.
From Uni, i recall working with a distibution looking like this, but i am not certain about the name.
I was hoping for something parametric where i can derive some simple parameters form the data (like mean and variance for a normal distribution)

I have made a histogram of the data:
![enter image description here][2]

(i know there is too little data for the small sizes)

Hope somebody have suggestions

  [1]: https://i.sstatic.net/ED5Oj.jpg
  [2]: https://i.sstatic.net/nkj6b.jpg