But this much-hyped hike by the US Federal Reserve (Fed) could be overshadowed by other momentous events.

Perhaps the most historic of these so far in 2015 has been the US Supreme Court’s decision in June to legalise same-sex marriage in all 50 states.

In the same month, the Supreme Court was busy ruling on the Affordable Care Act, also known as ObamaCare, which president Barack Obama has been trying to push through. The latest ruling is something of a landmark victory for a president who has extended healthcare insurance to cover millions more US citizens.

Candidates for the US presidential elections have also been generating headlines, ahead of the national election scheduled for November 8 2016, meaning President Obama has only a little while left in office to enact further measures.

What started out as a slow year in terms of economic data has turned into a more positive one, with firmer signs of growth coming out of the country. This has certainly fed into market expectations of a September rate rise, although there are plenty of economists expecting the Fed to hold off until December before raising rates.

David Jane, fund manager of the CF Miton Cautious Multi Asset fund, says: “In terms of the US economy, the various distortions of the first-quarter data are slowly being given proper context, as the data for the second quarter continues to build.

“The chatter will no doubt remain around the timing of any rate rises, with fears swinging between ‘too much too early’ or the Fed being ‘behind the curve’.”

Kully Samra, managing director of Charles Schwab UK, observes: “The economy is continuing to rebound after the weak first quarter, but the second quarter is no barn burner. But the US consumer may be coming out of [their] shell, highlighted by retail sales rebounding in May after a string of weak readings.”

He adds: “Even with the recent rebound, energy prices are substantially lower than they were last summer, unemployment is down, interest rates remain low, and wages are starting to rise – all supports for an improving consumer.”

US consumers then are reaping the benefits of a more buoyant economy. The question is how investors can also benefit from the economic upturn without being sidetracked by when or, how much, rates will go up this year.

The US stockmarket has actually been one of the best performers since the financial crisis, as Axa Wealth’s head of investing Adrian Lowcock points out, meaning it shouldn’t have been too hard for investors in US equities to find returns.

But so far this year, equity and fixed income investors have had a rocky ride.

Mr Lowcock advises: “Given the current levels of the US market, investors need a skilled fund manager to find those opportunities that still remain, whilst avoiding the expensive stocks and value traps. Stock picking is critical at this point.”

Ellie Duncan is deputy features editor at Investment Adviser