From Justin.P.Bryan@irs.gov Mon Oct 23 08:43:48 2017 Date: Mon, 23 Oct 2017 12:43:40 +0000 From: Bryan Justin P To: Daniel Feenberg Cc: Pierce Kevin K Subject: RE: data by state (fwd) The number of returns should add up, but you're right, the sum of the parts could be off because of rounding. I don't think I've seen it off by more than 3 as we usually check these to make sure we didn't make an error. I'm not sure I follow your Wyoming example. There was a disclosure issue for the $1-$10k cell so it was collapsed into the < $1 per our rule of collapsing into nearest smaller AGI category. For nonrefundable education credit and NIIT, the disclosure issue was in the <$1 AGI category so the cell was collapsed right into the next higher AGI category as there is nothing lower to collapse into. I can see why the last example of "** 40", "**", "**", "** 10","**" may be confusing with the wording of the footnote though. Following our rules for collapsing, the furthest ** on the right is collapsed into the 10 and the rest would be collapsed into the 40. -----Original Message----- From: Daniel Feenberg [mailto:feenberg@nber.org] Sent: Thursday, October 19, 2017 3:40 PM To: Bryan Justin P Cc: Pierce Kevin K Subject: RE: data by state (fwd) On Thu, 19 Oct 2017, Bryan Justin P wrote: > > The AGI categories do not add up to the total, so it looks like the > data was deleted, rather than collapsed but kept in the totals. So > there should be at least two sets of ** in any category to avoid > disclosure by subtraction. I worried that the sum provided might differ from the rowsum of the data because of rounding of the data, and I have not thought to impute it to the censored cells. Now I am not sure this is right. > > I'm not sure what year we started collapsing instead of deleting, but if > the parts add up to the totals, then it is collapsed rather than > deleted. If it is collapsed, our rule for collapsing cells for > disclosure is to move them to the next available AGI category that is > lower than the collapsed cell. So just to take your example below, they I think I see exceptions. Look at Wyoming 2015 where Alternative Minimum Tax is collapsed as you describe it should be, but lowest 2 cells for Nonrefundable Education Credits and NIIT are consolidated in the higher income cell. I wrote a lot of code to worry about this. Mostly it shouldn't make a difference, but there may be ambiguities if the rule isn't always followed. Also, the footnote says "Adjacent cell" which I took to mean that in the pattern: "** 40", "**", "**", "** 10","**" The first ** was consolidated with the 40 and the other **'s with the 10. I take it that you don't agree, the 40 consolidates the first 2 **s and the 10 only the last. This pattern occurs in Wyoming 2015 for Additional Medicare Tax, and in other places too. thanks for any clarification dan