SAN JOSE, Calif. — Daniel Jeremiah spends hundreds of hours watching film of NFL prospects and talking to coaches while preparing for his role as lead analyst for the NFL Network’s draft coverage.

He is also a Southern California resident with a son who plays high school football.

Personally and professionally, Jeremiah’s life is the Pac-12’s talent pipeline at its entry and exit points.

“You see some individual players” as good as those in the SEC and Big Ten, he explained recently when asked to compare the Pac-12’s high-end talent to its Power Five peers.

“You’ll get one here or there, but the difference is the waves of guys, especially on the lines, the defensive line,” he said. “The Pac-12 just doesn’t have the numbers.”

The Pac-12 has a number of numbers problems — from the number of teams it has sent to the College Football Playoff and the number of subscribers to its television network to the number of dollars it distributes to schools each year.

But there may be no greater long-term challenge to its marquee product than the shrinking number of participants in 11-player high school football within the conference’s six-state footprint.

Last winter, the Pac-12 Hotline took a deep dive into the decrease in participation in California.

The Pac-12’s primary talent pool experienced an 8.8% drop over five seasons (2013-17), largely because of concerns over head trauma, according to Roger Blake, who was executive director of the California Interscholastic Federation at the time.

“Moms and dads think there’s a risk being out there,” Blake told the Hotline, “so they say, ‘Go play something else.’”

The latest data, released recently by the National Federation of State High School Associations (NFSHSA), points to a continuation of the trend in California and an acceleration in surrounding states — including a momentous decline in participation in Washington.

According to the NFSHSA, participation in California dropped by approximately 3,000 athletes year-over-year and is now down 11.7% over the latest five-year stretch (2014-18).

Meanwhile, Florida, which feeds numerous Power Five conferences, has experienced a decline of just 0.6% over that five-year span.

Georgia, a key feeder state for the SEC (and others), has lost just 3.2%.

Meanwhile, Texas, the primary pipeline for the Big 12 and a vital recruiting ground for the SEC, has experienced an increase in participation over the five years.

• In fall 2014, there were 163,998 players in Texas (11-player tackle).

• In fall 2018, there were 165,641.

Contrast that to California:

• Participants five years ago: 103,740.

• Participants last fall: 91,305.

(Note: Figures are for boys only. In many states, a smattering of girls play tackle football, as well.)

The impact, Jeremiah believes, hits the Pac-12 hardest on the lines of scrimmage — especially the defensive line.

“It’s a quantity thing,” said Jeremiah, a former college quarterback who scouted for three NFL teams before moving to the TV side.

“Some of (the decrease) is due to head trauma, and basketball has some appeal. Some of the big guys are playing basketball.

“The ideal high school lineman isn’t the 6-foot-5, 320-pound kid. It’s the 6-foot-5, 250-pound kid who’s athletic and can grow into his body. And a lot of those kids are playing power forward (in basketball).”

Not only in California, it appears.

Oregon has experienced a 14% drop in participation over five years.

In Arizona, the decline is 11% in five years and 5.7% year-over-year.

“I don’t think you can say it’s all about concerns over head trauma, but that’s definitely a contributing factor,” said Dr. Javier Cardenas, a neurologist at the Barrow Neurological Institute in Phoenix who works as a sideline physician for Arizona State football and serves on the NFL’s Head, Neck and Spine committee.

“The message we’re getting is that it’s all contact sports, it’s not exclusive to football.”

Ominous as the numbers in California and Arizona might be for the Pac-12’s future — the conference is funding research into head trauma prevention and recovery — the steepest year-over-year decline unfolded in the Northwest.

Prep football participation in Washington plunged 21% year-over-year, according to the NFSHSA: from 23,282 tackle football players in fall 2017 to 18,348 last season.

So dramatic is the change in participation — the drop followed a slight increase the previous year — that the Hotline reached out to the Washington Interscholastic Activities Association (WIAA) for confirmation and context.

Casey Johnson, sports director for the WIAA, said via email that the organization is “still looking into verifying that number” but that it was reported to the association by athletic directors at high schools throughout the state.

“There is definitely going to be a margin of error with the number but we can only use information reported to us,” Johnson added. “We will continue to look into the drop in football specifically, as well as our reporting mechanism in the future.”

Asked to explain the apparent decline, Johnson said:

“Assigning a reason for the drop would just be speculation on our end since we don’t have data one way or the other.”

It is not difficult to guess one of the reasons, if not the primary reason.

For the past four years, the Barrow Institute in Phoenix has surveyed parents and teenagers about their sentiments on concussions.

Arizona parents who would not allow their children to play tackle football:

2016: 30%

2017: 32%

2018: 38%

2019: 40%

Cardenas said concussions and catastrophic brain injury remain a concern but are no longer the primary issue.

“There has been a shift to concern over the chronic, long-term effects of head impact,” he said. “Repetitive head impact is clearly on the minds of parents, whereas five or 10 years ago it was about concussions.

“The emphasis has moved away from the catastrophic to being more concerned about the chronic effects.”

The drop in participation is not universal: The numbers in Utah are holding steady, while Colorado has seen a slight uptick over the past five years.

But overall, participation in the six Pac-12 states is down 10.3%.

Put another way:

Last fall, there were 4,000 more high school football players in Texas than in the entire Pac-12 footprint.