Frontier market economies - a cluster of 56 mostly middle-income economies - have on average achieved less than half the rate of investment growth per person in the 2020s than the rate achieved in the 2010s, says international finance institution the World Bank. Over the past 25 years, the growth rate of investment per person in these economies has ratcheted down, dropping to just 2% in the 2020s, which is less than half the rate in the previous two decades.