I&#x27;ve specified &quot;agencies&quot; since my first comment, not the CBO. In the US, those are separate branches - executive vs legislative respectively - and use different approaches to build their &quot;baselines.&quot;<p>CBO assumes the government continues current operations and applies the effects of new laws to create their baseline.<p>Agencies include discretionary spending to create their baseline.<p>All of this is noted on the Wikipedia page.