Ordinary people spend only a few hours during the life of a parliament thinking about how they will vote when a general election is held. This does not mean that their mind is a political blank sheet that can be filled by tweets by parties and shouted exchanges by party leaders. When it comes time to vote, people draw on their own experiences over the past five years to decide how to vote.
People do not need to wait for the media to broadcast monthly economic statistics to know what's happening to their cost of living. They learn about it every time they check out at a supermarket or put petrol in their car. They learn at first hand that the cost of living is going up. Each month their credit card bill summarizes how much their bills are going up and their monthly bank statement can confirm that the pot of money they have been saving to replace a worn-out car is shrinking.
The prime minister can be factually correct to say that the monthly rate of inflation is going down from one month to the next, but this ignores what matters to ordinary people: the cumulative effect of rising prices on inflation from one year to the next. By the most favourable measure, consumer prices have "only" gone up 23 percent since 2019. However, the costs that people see weekly, food costs, have risen by more than 30 percent since the last general election.
Statistics may show that average wages are rising at a faster rate than inflation but ordinary people may see the opposite in their payslip. Up to one-third of a pay rise is likely to be deducted in marginal income tax and national insurance contributions, and upwards of one half of the increase will go in tax if a person is pushed into a higher rate band. Moreover, the millions who are on variable rate mortgages have experienced worse: their disposable income can fall sharply when their monthly mortgage bill rises.
The contrasting ways that politicians cite statistics does not necessarily mean that the numbers cited are false. Each chooses sets of numbers that are most favourable to their own party, whether it be the direction of change from one month to the other or the cumulative extent of change over the life of a parliament. But neither is the most effective way to communicate with voters.
Ronald Reagan showed the best way to talk about the cost of living was to avoid numbers and ask voters a question about their own experience. In a debate with President Jimmy Carter he turned straight to camera and advised people that when they got a ballot in their hands to ask themselves: "Are you better off today than you were four years ago?" PS: Reagan won.
Prof Richard Rose, University of Strathclyde Glasgow, has been writing about ordinary people in public policy for more than half a century.