For a man who values his accumulation of data so highly, there is one statistic that will stalk Sam Allardyce for as long as he holds on to his precious new role. As he contemplates its significance, it will give him an insight into the challenges that confronted his predecessor. He has his dream job at long last but this number is the stuff of nightmares for any England manager.

There can be no excuses for the way that Roy Hodgson bungled England’s chances of succeeding at Euro 2016 in isolation. In a wider context, though, Hodgson’s underachievement cannot change the fact that he was selecting a squad from a dwindling pool of homegrown talent, with the number of English players starting in the Premier League dropping to 31% last season. That is an average of just over 68 players a week and at this point Allardyce could be forgiven for wondering if this job is all it is cracked up to be.

Though the 61-year-old discussed the topic openly, he struck a concerned tone at first. “The only way we get a bigger pool is by us in the long term producing more players in our own country,” he said. “Unfortunately, because the Premier League is a global commodity, it can be filled up with international players at all levels.

“Even at academy levels, there are foreign players being taken in. That’s growing quite quickly, which is quite disturbing. But they are having to look after themselves and their brand. It’s a worldwide brand. So it’s a huge task for us and the FA to break that cycle. We have to keep trying.”

Allardyce did not have a reputation as a great champion of young players at club level. Mark Noble and James Tomkins were established academy products who matured under his guidance at West Ham United and he bolstered the English contingent there by adding Andy Carroll, Aaron Cresswell, Stewart Downing, Matt Jarvis and Kevin Nolan to the mix in the years after promotion.

There were opportunities for Duncan Watmore and Jordan Pickford at Sunderland, while Allardyce’s time at Blackburn Rovers was notable for the trust he placed in Phil Jones by giving the defender his first league start in a game against Chelsea, whose attack featured Nicolas Anelka and Didier Drogba.

Yet he did not have an English core at Blackburn Rovers. “Bolton at one stage, we hardly had any,” Allardyce said, before explaining that English players were often too expensive for the smaller clubs. “They were cheaper from abroad. What does your budget say? The budget is the underlying factor. You’d like that player – but he’s 25% more than that one here.

“I bet most of the England players in the Euros were loaned out early in their careers, or they started in lower league. We have lost the emergency loan system which we have to fall into line with Uefa sadly. All those youngsters aren’t having any first-team experience. We are blocking the way for our youngsters to develop. We’re looking at a player coming into the Premier League at 22, 23 now. If you didn’t make it at 18 when I was coming through you were gone.”

It means that he might have to compromise and pick players who are struggling for games. “I talked to Roy many times about the fact you are often picking with some who are at the top of their club, but some who are fringe players as well, rather than regular players,” Allardyce said. “That goes without saying now when you’ve only got 31%. Now I’m sat in this position it’s disappointing. I’ve just come from the Premier League and the pressures that come with that.”

At the same time, Allardyce believes his youthful squad is bursting with potential and hopes to discover more hidden talents such as Marcus Rashford. “It’s fair to say that if [Anthony] Martial hadn’t got injured in the warm up [against Midtjylland] we wouldn’t have seen the young man playing for Manchester United quite as much and ultimately playing a couple of substitute appearances for England,” Allardyce said. “What an exciting prospect he looks. How many more of those players are there that can maybe emerge? I get excited by that.

“But I also get excited by it being the injury crisis at United forcing those lads to be thrown in at the deep end and obviously he came out on top. It’s not easy to put those youngsters in as a Premier League manager because of the cost of failure but when you get someone emerging like that it’s encouraging to think that talent is lurking.”

But Rashford’s opportunities under José Mourinho might be limited after Zlatan Ibrahimovic’s arrival. “It will just be down to him,” Allardyce said. “He’s a talent. If he sees that talent emerge like it did last year he picks himself. Where he [the manager] might play him might not be as much as last year. He’s brought some terrific players, particularly Ibrahimovic, a big frontman. His job is to win the title with United now.”

Therein lies the problem.