The current histogram dimension input is very picky about how you handle calculated dimensions - nearly always requiring an Aggr statement to work. There are many situations where a simple if statement would be natural to use a filter but does not work in the current implementation.
For example, if you wanted a histogram bucketed by [Age] but only wanted to see hourly associates, having =IF([Associate Type]='Hourly',[Age]) is something that intuitively works but doesn't in the current implementation.
