I am trying to merge US Census data from 1930-2010, so I can create a temporal layer that shows how the populations changed over time. I have a census layer for each decade and when I merge them I get null values for all the datasets aside from the first one in the merge. I particularly need the % Non-White field. I checked the data types and they are all numeric. I tried appending and that didn't solve the issue. I also tried joining that got nulls again. Is there another way I can create a temporal display without having the layers combined? Maybe this isn't possible because the size of the census blocks have changed significantly over time. I'm going to try to export the merged table into excel and copy and paste the percent non-white numbers from the original layers tomorrow. That should work, but it's not the most efficient.