Has anybody else noticed a decline in Wikipedia's placement on many Google search results?

More often than not I want Wikipedia as my first result, both as a cross-reference for anything else I click on and as an index for other useful or interesting links. They were consistently in the top 5 results for anything that actually had a Wiki page for years, but now I have to pull the top few pages or even write `$query wiki` to get Google to reliably bring Wikipedia up.