My guess too is that the right quote is the problem. As I type right
quote basic ' it is a quite different character from what you have. 
If you download the invaluable -asciiplot- from SSC 
you can get a display of characters for your machine. 
I think you are getting char(146) when you want char(39), except that
146 may take a different value on your machine. 
Nick 
[email protected] 
Kyle K. Hood
This code (within a do-file)
. sum year
. local minyear = r(min)
. local maxyear = r(max)
. local yrdiff = `maxyear' - `minyear' // T-1
Generates the following result (and error):
Variable | Obs Mean Std. Dev. Min Max
-------------+--------------------------------------------------------
year | 2244 1979.5 12.70126 1958 2001
`maxyear' invalid name
r(198);
When I type the same code on the command line, I don't get the error -- 
however, when I erase and retype the code within the do-file, I get the 
same error. I am running Stata/SE 9. I really have no idea what is going
on. I have scrutinized for spelling, etc. The code that I sent was 
copied out of the do-file directly. I do wonder about the right single 
quote (it looks funny), but I am using Stata's do-file editor, and am 
using the single-quote-key directly to the left of the "enter" key. Can 
anyone help?
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