A gigantic wealth transfer over the next two decades will make millennials 'the richest generation in history', a new report has revealed. 

Millennials in America alone will inherit a huge $90 trillion from property, shares and other assets over the next 20 years, according to the annual wealth report from real estate consultancy Knight Frank. 

Baby boomers - those born between 1946 and 1964 - and the so-called silent generation - Americans born between 1928 and 1946 - will 'hand over the reins' to millennials born between 1980 and 1996, it said.

It comes as many younger people - millennials and Gen Z adults - are struggling to hit the same milestones as those from previous generations. 

Soaring inflation, student debt and an unaffordable housing market have meant many young people have found it difficult to buy their own home or build up savings. Around 90 percent of housing stock is owned by over-40s, while 74 percent is owned by Americans over 50. 

Baby boomers are famed for benefiting from great social mobility when house prices were low and labor conditions strong. 

Figures from the Federal Reserve and wealth management firm Cerulli Associates, show that US households hold $159 trillion in assets. 

Of this, boomers hold $78.1 trillion, while millennials hold just $13.3 trillion. 

The silent generation, meanwhile, hold $18.6 trillion, while Generation X - those born between 1965 and 1980 - hold $46 trillion.

In recent years, a narrative has emerged that young Americans spend too much of their money on expensive coffee and avocado toast. 

But the wealth disparity is largely attributed to rising property prices, which have shot up by around 500 percent since 1983 - when boomers were in their 20s and 30s and just getting onto the property ladder.