If you are searching for a specific numeric value within a facet, and the facet search is not retrieving the exact match as a top or only result, consider the example where the facet contains the value '2002.' Although it exactly matches '2002,' the search results do not display '2002' as the only match, and it is not shown at the top of the results.
This is because by default, the allowTyposOnNumericTokens parameter is set to 'true'
When you can turn it off, searching for the value '2002' will only retrieve the value '2002'