Table 4.2 summarizes some recent estimates for (mainly) economic infrastructure investment at the global level and by sector, which suggest annual needs ranging from $4.6 trillion to $7.9 trillion.11 This range includes estimates using both baseline and low-carbon scenarios. For obvious reasons, all such estimates of future needs for infrastructure investment have problems related to coverage, assumptions and methodologies. There is lack of clarity about the definition of infrastructure and types of investment considered, as well as lack of comprehensive data on current infrastructure investment.