What should be the default option of an optional dropdown list containing search criteria?

Question

I have a form where users can search for legislators in the US. One of the search criteria is the Leadership Position, as a dropdown. It can look like this for example:

<select id="leadership-position">
    <option value=""></option>
    <option value="10">Assistant Minority Leader</option>
    <option value="66">Majority Conference Chair</option>
    <option value="68">Majority Conference Secretary</option>
    <option value="72">Majority Leader</option>
    <option value="80">Majority Whip</option>
    <option value="89">Minority Conference Chair</option>
    <option value="92">Minority Conference Vice Chair</option>
    <option value="96">Minority Leader</option>
    <option value="106">Minority Whip</option>
    <option value="111">President Pro Tempore</option>
    <option value="138">Speaker</option>
</select>

Whenever the first option is selected, then all legislators are displayed in the search results. When some non-blank option is selected, only legislators having that Leadership Position are displayed in the search results.

In such a case, what is the best text to display for the first option? Blank? I think it's the standard, but had some user feedback that this is confusing. What about "Any"?

Answer 1

If the control is an optional filter, then searching with the default means that you will see results for all leadership position types.

When a user looks at their filter, it is nice for them to be able to immediately understand what is included in their results set. To make this clear, the text for the default option should contain the word "All".

Answer 2

Having it blank is fine. Personally I like to use a few dashes. I've also seen (All Positions) as the text.

The main thing is to make sure it is consistent throughout your entire application. That way the user only has to learn it's meaning once.