question about dataelement aggregation level

I have an issue regarding dataelements which are entered at both
health centre and district hospital level. In order to see the actual
data at district hospital I have set the aggregation level for this
dataelement to the levels above district hospital. Is this a correct
interpretation of the manual. Doesn't seem to be working for me ie.
the district hospital is still showing the aggregate value of the
health centres.

Using 2.7 stable.

Any ideas?

Bob