Companies have saved $474 million since 2018, with most of the windfall going to Washington-based tech giant Microsoft. Lawmakers repeatedly expanded who qualifies, and they lowered the number of jobs expected in return.

State lawmakers nearly unanimously passed the special exemption and have kept the benefits flowing to the industry ever since. But the tax break has strayed from its original promises, and the state failed to fully scrutinize whether the sacrifices were worth it, a deep examination of legislative archives, public tax disclosures and utility data by The Seattle Times and ProPublica revealed.

The data center industry’s demand for electricity is growing so much that it could threaten Washington’s efforts to transition to a carbon-free power grid, the news organizations recently reported.