jQuery - reusing change() function

Hello Experts,

If someone can give me advice on the following.

I have several selects:

<select id="search_1_unit">
...
</select>
<select id="search_1_m">
...
</select>

<select id="search_2_unit">
...
</select>
<select id="search_2_m">
...
</select>


<select id="search_3_unit">
...
</select>
<select id="search_3_m">
...
</select>


When the user selects a 'unit', I have an .change() jquery function that kicks in and dynamically populates
the search_1_m select.

ie
      $('#search_1_unit').change(function() {
      
      };
      

How do I rewrite this so that I don't have to write a
new function for each select.

ie I don't want to code:

      $('#search_2_unit').change(function() {
      
      };
      
      $('#search_3_unit').change(function() {
      
      };      
      
etc

Many Thanks as always!