Roughly 40% of the projects announced in the first year of the implementation of President Joe Biden’s largest industrial and climate infrastructure spending bills have been put on hold, according to a new analysis that illustrates the difficulty of translating major subsidies into physical construction.

During the 117th Congress, Biden signed the Inflation Reduction Act and the CHIPS and Science Act, which together offered more than $400 billion in subsidies for clean technology and the domestic buildout of semiconductors.