The phrase "almost every prior" is correct and usable in written English.
It can be used when referring to nearly all previous instances or examples of something.
Example: "In almost every prior study, the results indicated a significant correlation between the variables."
Alternatives: "nearly all previous" or "almost all earlier".
Imagine reading a controversial news story on climate change and later finding out that the scientist, whose findings you are reading about, had seen almost every word prior to publication.
Almost every issue published prior to 1940 contains something inimical to felicitous intergroup relations--rapacious Jews, ten-watt blondes, no-account blacks, shrewish housewives, and so on.
Almost every characteristic of Prior is designed to challenge Rivers in ways that his other patients, who revered him to the point of idolatry, were incapable of doing.
Almost immediately it outsold every prior release in Merge's 15-year history.
He suggested in a court filing that "Vincent Astor was drunk almost every afternoon for several years prior to his death," and that he had reason to believe "that persons were taking advantage of him on many occasions".
"We've experienced one of the busiest starts to the year since we opened five years ago, as almost every buyer wants to complete prior to the increase," says James Pace from Knight Frank's Chelsea office.
According to a recent report by the National Lawyers Guild, the "violent anarchist" narrative is used by authorities prior to almost every large political demonstration in order to justify "enormous security expenditures, large numbers of police, and strict event zone ordinances".
Once or twice a show O'Reilly will interview an adversary (such as the aforementioned president of the atheist association) and eventually bully him with righteous indignation and even name calling, and prior to almost every WWE match there is the spectacle of two alleged warriors yelling insults and life stories at each other to fire up the crowd.
Whereas 23 of 32 team physicians did not perform any injections for musculoskeletal symptoms during the 2014 World Cup, 8 four players from one national team received peritendinous or intra-articular glucocorticoid injections prior to almost every match.
For Afghan boys with almost no prior schooling, the pressure is enormous.
