Thank you for your answer.
The following results were obtained using oaxaca_rif.

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overall
group_1 | .2900839
group_2 | .2913806
difference | -.0005414
explained | -.0574823
unexplained | .0569409
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I understand what the following example means.
- for example difference 0.05, explained 0.02, unexplained 0.03 (unexplained ratio = 0.03/0.05*100)
But I do not know what it means to be a negative number.
How can I get the unexplained ratio? (0.569/-0.0005414 *100 ?)

I'm sorry for starters...
I hope to help you