The Cost of Political Polarization: Historical Data Points U.S. legislative productivity has declined measurably since the 1990s—Congress passed an average of 297 laws per session in the 1980s versus 105 by the 2010s, according to Govtrack data. This correlates directly with increased partisan voting patterns; in 1970, roughly 30% of Congressional votes were strictly along party lines, whereas by 2020 that figure exceeded 80%. The partisan gap mirrors the broader electorate: Pew Research found that in 1994, only 21% of Democrats viewed Republicans negatively, compared to 60% by 2021. Why it matters: Gridlock reduces government's problem-solving capacity on infrastructure, healthcare, and economic policy—historically, bipartisan legislation has produced more durable solutions. When voters perceive politics as purely tribal rather than issue-based, it erodes faith in institutions themselves, creating vulnerability to institutional destabilization.