The political scientists Jane Green and Will Jennings have an interesting project tracking evaluations of political party competence in the US, UK, Canada, and Australia. Here’s a description:
This project gathers over time data from opinion pollsters in four countries; the U.K., the U.S., Canada and Australia, about voters’ ratings of parties on policy competence and handling. Using an established method of estimation and aggregation, these data provide continuous time measures of policy competence spanning periods up to six decades. Analysing them enables us to understand how parties gain and lose reputations for policy competence, how policy competence ratings may decline during a period of government, how the concept varies across countries, and how policy competence ratings change with other performance indicators, for example, leader ratings, events and economic outcomes.
Here are some results for the current incumbent parties in the UK and US:
The data is also freely available.
[Cross-posted at The Monkey Cage]