According to Gates, the impact has been significant. In the space of 19 years, for example, the number of deaths of under-fives living in low- and middle-income countries has fallen 40 percent. Meanwhile, deaths caused by AIDs have halved since the turn of the millennium and polio cases have shrunk spectacularly, with only 31 reported in the whole of 2018.
"Obviously, the key thing here is that they’ve saved lives," Gates wrote. "But they’ve also been successful in the way that investments traditionally are: They’ve created a lot of wealth, because when people aren’t sick in bed, they can go to work or school."
Based on calculations made by the Copenhagen Consensus Center, a nonprofit think tank that examines and prioritizes solutions to global problems on a cost-analysis basis, Gates has been able to compare the economic success of these initiatives to those of other possible solutions. For example, had that $10 billion been invested into energy products, the return would been $150 billion. Infrastructure, $170 billion. Standard & Poor's 500 (with the balance given to developing countries 18 years later), a measly $12 billion – or $17 billion if you include dividends.
Instead, by investing that $10 billion into the buying and selling of medicine and other supplies, they have reaped approximately $200 billion in social and economic benefits. And, we have to say, that is pretty impressive.