The citizens of the Indus Valley Civilisation, a permanent settlement that flourished between 2800 BC and 1800 BC, practised agriculture, domesticated animals, used uniform weights and measures, made tools and weapons, and traded with other cities. Evidence of well-planned streets, a drainage system and water supply reveals their knowledge of urban planning, which included the first-known urban sanitation systems and the existence of a form of municipal government.[58]

Portfolio income can come from multiple sources – interest/bond coupons, stock dividends, financial strategies including derivatives and capital growth.  Each offers some cash flow and some also offer potential capital gain with some risk from liquidity and volatile prices.  In this low-yield environment, many investors rely too heavily on cash flows and to pursue this are venturing further into riskier areas than they’d normally consider.