Material Allocation on Histogram Problems

Hi All,

I am allocating material quantities to certain activities on the bar chart in order to produce a histogram.  I am putting the total material quantity total in the correct column, however in the histogram it is picking up the total quantity in each day.

For example I have an activity where a certain slab pour contains 50 tonnes of reinforcement bar.  The fixing of rebar for this activity is 6 days, so it should show about 8.3 tonnes a day, but it is just showing 50 tonnes for each day? Can anyone help as to which setting I need to click to show what I want, as I cant seem to find the right setting.

Any help would be much appreciated.

Thanks