The G-20 aims to take stock of the G-20 economic recovery. One achievement in Pittsburgh could be

Question:

The G-20 aims to take stock of the G-20 economic recovery. One achievement in Pittsburgh could be a deal to require that financial institutions hold more capital.
What are the financial institutions that the G-20 might require to hold more capital? What exactly is the “capital” referred to in the news clip? How might the requirement to hold more capital make financial institutions safer?