I have a string variable that in the data editor in STATA appears to be right aligned for some observations.  There are blanks before the actual values.  I was trying to merge two files and ended up with the variable us_id like this. It did not merge correctly. The first 6 observations should have merged and the last six observations should of merged as well. Any ideas?  I think I need to use ltrim but not sure where to put the ltrim() at? 
For example, I have the variable us_id;
us_id
00050
00010
00020
   00050
   00010
   00020
00060
00070
00080
   00060
   00070
   00080
Thanks,
Marilyn. 
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