It warned that the British capital’s pull was waning amid concerns that fewer companies were choosing to list in the UK.
However, figures from the London Stock Exchange show that only 22 UK companies have floated in the US in the last 10 years, and their shares are 39pc down on average.
The figures suggest that talk of an exodus is overstated – but nevertheless, the recent exits are symptoms of deeper issues.
Startups have prospered in the UK, which boasts 135 unicorns valued at $1bn or more. This is more than France, Germany and Singapore combined.
These factors suggest that while Britain is good at creating companies, there are issues around scaling and growing.
“There is a problem with the ‘investability’ of British business and the size of our stock market,” says Lord Hammond.
One reason, he says, is that a typical well-off middle-class household in Britain “may well have no significant financial assets other than a home and a pension”.
“In the US, that same household on an upper middle income would typically have a portfolio of financial investments as well,” Lord Hammond adds.
Regulatory changes over the past two decades also mean that UK pension funds increasingly allocate funds to supposedly low-risk assets such as government bonds, rather than investing in British companies.
While much has been said about Britain’s troubles, narrowing the growing gap with the US is still possible, according to economists, politicians and business leaders.
Lord Hammond says one place to start would be to change the rules for pension funds so that they can invest their money more widely.
“Our pension funds in the UK often allow people to retire at 50 or 55, contrary to public policy, and do not invest their funds in UK markets and UK businesses, contrary to public policy,” he says.
“So if you want to save your money without tax relief you can do absolutely whatever you like with it as far as I’m concerned. But if you want the support of public policy through tax relief, you need to accept some constraints which align your saving activity with public policy agendas.”
But the key thing will be to make work more productive, he says.
“If we want to have high standards of living, reasonable taxes, and good quality public services, the only way to deliver that is to have rapidly rising productivity,” he says.
Economists and politicians have many different views on how to boost productivity and thereby growth to put us on a more similar trajectory to the US.
Boosting Britain’s patchy business investment record is critical, according to Neiss.
Another option is devolving powers to areas outside London to boost growth, says Michael Heseltine, a lifelong Conservative politician who served as deputy prime minister.
“Significant parts of England and the rest of the United Kingdom lack the incentive to create conditions” for boosting growth and opportunity, he believes.
“The one big domestic agenda available to the Government is to speed up the mayoral authority process and the devolution of power from London to those economies,” he says.
Jeremy Hunt, the Chancellor, set out plans to address some of the supply-side issues Britain faces in his “Budget for growth” earlier this year, although many economists believe much more will be needed.
City minister Andrew Griffith says the Government’s Edinburgh reforms, which seek to overhaul regulation in the City post-Brexit, will build on existing strengths by “enhancing access to market information, helping hire the best global talent, and making it easier for companies to raise capital”.
Companies choose the UK because it is a “global financial hub and a safe place to do business,” he says, adding: “The London Stock Exchange dates back to a time when the USA didn’t exist.”
But with Labour polling 18 points above the Conservatives, shadow chancellor Rachel Reeves could soon be the person in charge of restoring growth and convincing workers and businesses to choose the UK.
Her pitch is that Britain must “show global leadership” in the race for the green industries where the “US and the EU are stealing a march on us”.
“Some country is going to be a leader in green steel, carbon capture and storage, in wind power, in electric cars, why not Britain? We should be attracting business investment here – instead we’re left in the changing rooms while other countries are out on the track,” Reeves says.
Mr Hunt has said that he will present measures in response to the US and the EU’s vast green subsidies in the Autumn Statement.
The US has been very good at “picking winners”, KPMG’s Sarson says.
“We’ve got to think about which industries we really want to support and then go full in with both feet rather than sort of dabbling here and there.”
The most important aspect of any future approach to fixing Britain’s anaemic growth and catching up with the US will be consistency, however, says El-Erian.
“One thing to remember is this is not a one-off thing. You’ve got to keep going, keep going and keep going. And you’ve got to learn from what has happened,” he says.
Britain’s past holds many of these lessons. But without major reform, the hope we could all become richer than Americans will be an increasingly forlorn one.
