After 61 focus groups for New York Times Opinion, listening to voters on the Biden presidency, Donald Trump and Kamala Harris, and holding sessions with police officers, teachers, “Yellowstone” fans, young women, Black men, transgender people, tweens, 80-somethings and many others — what did we learn from it all?

Little did we know that our very first focus groups, in January 2022, would anticipate the frustrations and desire for change among the 680 people we’ve talked to over nearly three years.

“The economy started to go bad,” said Judi, an Oklahoma Republican, recalling what she remembered most from 2021.

“My grocery bill is through the roof,” said Jules, a Virginia independent.

“You can’t afford it,” said Sue, a Kentucky Democrat, talking about Covid tests.

“I’ve had Covid multiple times, and I’m concerned with that, but inflation is hitting us every day,” said Nick, a Pennsylvania independent.

The worst of the pandemic may feel far away now, but as we look at the Harris versus Trump contest on Tuesday, Covid is the essential prism through which to understand the trajectory of the last three years in America. The pandemic felled Mr. Trump in 2020, bringing out the true autocrat for all to see on Jan. 6, 2021, and fueled his hunger for the second term he felt he was owed. Covid shaped the economy that Mr. Biden tried to revive through policies that proved inflationary. The shocks and aftershocks of the lockdowns and closures set many of our focus group participants on harder paths in life, from schoolchildren to college students to workers to the elderly.