Helicopter cash, climate crises, smart cities and the space economy - investors have all those possibilities ahead as they enter the third decade of the 21st century.

They go into the new decade with a spring in their step, after watching world stocks add over $25trillion in value in the past 10 years and a bond rally put $13trillion worth of bond yields below zero.

They also saw internet-based firms transform the way humans work, shop and relax. Now investors are positioning for the tech revolution's next 10 years.

Could we see a repeat of the roaring twenties, as the 1920s were known - years of prosperity, technological innovation and such social developments as women winning the right to vote?