If your looking to find if this distribution is likely a uniform distribution, this looks like a job for Chi square test.

Dealing with absolute values (

**updated** from "percentages" to meet what I posted):

`Sum of ((observed - expected)^2)/expected)
dividing by df (number of degrees of freedom
`

Since you have 19 classes, df = 18 the Chi square statistic is:

`X-squared = 38297.18, df = 18, p-value < 2.2e-16`
And that very small p-value indicates it does

~~not~~ depart significantly from a uniform distribution...

**Updated** originally got it backwards, as Anonymous Monk pointed out. Hence the following also became a moot point

**However** if the the same hump was to be observed over and over again, then my suggested approach was probably not the right one to follow, a real statistician might have a better insight. (That last part still holds ;-)

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